Best camera

I like the Panasonic Lumix line. I have an older one so I'm not sure of the most recent model number. They're compact, easy-to-use and they take really clear shots.

What's not great about the one you have?

I like my Canon S120 -- makes nice video, too. It has a nifty "Hybrid" setting that automatically records four seconds of video every time you take a still photo.

But whatever you get, pack your old one as a spare. On my last trip to Europe my S120 acquired a nasty dust spot on the sensor while we were still on the flight over to Rome. So the S120 went into the bag, and I put my old Samsung WB150 into the game. With a little help from post editing with Photoshop and Aurora it did fine.

If your problem is low light, (you mentioned using it at night) a "general rule" is the bigger the sensor the better. Short of taking a full size or very expensive camera, I would recommend on of the all-in one's which have a micro 3/4 (or close to it) size sensor. Of course, you could look at the micro 3/4s. When I travel I prefer all-in-one cameras with no changeable lenses. Take a look at the Panasonic Lumix DMC-FZ 1000, one of the Sony Sony DSC-RX10's or Sony DSC-RX100s. Yes they are expensive, but they are not point and shoot. They have larger sensors than point and shoots, take RAW, and have full manual control (as well as things like better lenses than a point and shoot.) These are IMHO decent options for someone who enjoys photography. There are a myriad of other choices if you want to improve your travel pics without spending lots of money. These cameras will not compete with full frame, but the first two I listed are pretty much an "all in one" package and the RX100 will fit in your pocket. Good luck and keep snapping!

Much depends on your budget and requirements.
A good travel option for the masses would be the Sony Rx100 series (I would recommend the III version over the IV unless 4K video is a priority for you), still a little more complicated to learn than your typical P&S but can also taker better pictures.
Price no object, the Sony Rx1rII would be impossible to beat in IQ for it's size.

What model powershot. Those cameras have generally received high reviews. What is the deficiency you noticed?

It's not the camera that makes the picture. It's the photographer. You could buy the most expensive camera out there but if you don't take it off "auto" then there's no point in owning that expensive piece of equipment. I have seen plenty of people with very expensive cameras doing just that and getting poor results. My sister in law has an iPhone and takes awesome photos. Whatever camera you choose to buy, make sure you have time to learn how to use it before your trip.

As Ray and mreynolds have said, the Sony RX100 is a fabulous all around camera, and it really excels in low light situations. The base model (RX100) is all you need, though wifi ability may be desired. Without knowing more about your requirements, and what it is about your current camera that comes up short, that would be my suggestion. It's certainly possible that a less expensive product would be a big improvement for you too.

Edit: ^^^ Mary makes excellent points, and it is especially true in low light situations that understanding manual operation is critical. With the Sony model mentioned, however, in average well lit shots, "Auto" works quite well and to me that alone would be worth it-but that's just me.

http://www.bhphotovideo.com/c/product/869238-REG/Sony_DSC_RX100_Digital_Camera.html

You didn't say when your trip to Ireland is taking place, but if there's time I would suggest (expanding on Mary's comment) that you take a digital photography course of some sort - check out your local arts council or community college. Once you gain a better understanding of photography, your pictures will improve.

I totally agree, the photographer is the biggest piece of the "good pic" puzzle. That being said, there are a number of situations where the camera makes a big difference in what shot will/won't be blurry, have a lot of noise, etc. Whatever camera you get/use, learn everything you can about it and photography in general. But don't forget the camera helps.

I second the Lumix brand camera. I got mine in 2006-ish and it still works great after being dropped, shoved in packets/backpacks, used in light rain etc. Its also easy to learn.
But
I outgrew it and now have an entry level DSLR from Nikon.
I would suggest getting something with a zoom/telephoto option.
J

BTW - I used to have a Canon Powershot (gave it to some young relatives, and got myself a Canon SL1). With the Powershot, I found that the pictures looked pretty dismal on the view screen, but then looked fine when I got them onto the computer for editing. Had you tried that, or only looked on the view screen? Also wanted to note that the SL1 is really small and light for an SLR, so I like it for travel. That being said, I still very much recommend taking a photography class of some kind.

We have a Panasonic Lumix DMC-FZ70 which is not a pocket camera, but lightweight and takes a nice picture. It has a 60x optical zoom and and a very effective 20-1200 range. We took good photos of animals,on a trip to Kenya, that were REALLY far away.

However, if you really want high quality pictures (that you can manipulate) and you really want the picture to be what you see through the viewfinder, nothing beats a DSLR. We have a lower end Nikon D5000 with a Tamron 18-270 lens and it will take better pictures in more environments and with better quality than any other camera I ever owned. This camera has been discontinued by Nikon for newer models but you can still buy a new one for about $365. There are similar Nikon Models currently made.The Tamron lens is now down to about $365.
The Panasonic is about $250. It would be seem to be a shame to make a trip of a lifetime and not have a decent camera to record it.

Good luck.

I hesitate to to add, but will, that you should consider having a backup camera to your primary photo device-accidents and thieves happen. For these reasons, it's also a good idea to have multiple camera cards and switch them out periodically-all your eggs won't be in one basket. You can get a plain camera strap with steel bands running through it that can't be easily cut and run away with-and it's not a good idea to go walking around with a strap shouting "I have an expensive Nikon/Canon camera over here!".

I second the recommendations of not putting all of your eggs in one basket. I had a nice point & shoot camera and my wife and I had iPhone cameras. On the last night of our tour of Italy, while changing my clothes, the camera came off my belt and fell into the toilet. It was in a case, but that didn't stop the water from getting to the camera. I immediately took out the SIM card and did everything recommended to save the camera. Unfortunately, the camera was ruined, fortunately the SIM card was still good. Even if the SIM card was ruined, we had taken up back-up pictures of everything on the iPhone cameras. Accidents happen!

I'm a fan of the Canon Rebel series. Good bang for the buck, and easy to use.

I'm really enjoying the Canon G9X which contains a 1 inch sensor yet truly fits in my pocket. It's the most travel friendly of my collection. It helps me keep my carry on weight under 26 lbs while offering better quality than my phone! The retro silver is very attractive as well. http://www.trustedreviews.com/canon-g9-x-review