When you compare tours make sure you are comparing apples to apples. I've done 11 Rick Steves tour and 11 Road Scholar tours. I continue to travel with these companies because they are smaller groups (24-28, sometimes less), have tips included and don't have all the good sights being sold as "optional" tours. Neither have "shopping" stops where the guides get a kickback for bringing you in. Both are pretty explicit about what sights/admissions they cover. I've gone solo on all the Road Scholar tours and about half of the Rick Steves tours and have had wonderful experiences.
Rick's tours have fewer meals included and that suits me. Road Scholar has many meals although the last one I did there were several nights on your own which I like. Sometimes I just need a lower key meal.
Tips- If the tour company doesn't say it includes tips, figure $7-10/per person/per day for the guide, $3-5 for the bus driver.
Optional tours - Check to see if they advertise optional tours. If you don't pay for this tour, you may miss out on seeing the good sites at a location. I've seen some complaints on Trip Advisor where people weren't expecting this and then were shocked when the tours to see the "good stuff" were several hundred dollars more. Just do your research on this.
Also know "tour brochure" speak - To View a site is to do a drive by. To SEE a site is usually going in to visit it. Rick and Road Scholar do not use tricky language. You may find other companies that are up front about what their tours see as well.
Almost all tours count the final day as a "day" on the tour. It's generally just breakfast and no planned activities. I have had some Road Scholar tours that had a short program on the final day (usually the birding programs).
If you are not sure about how much you'll enjoy a group dynamic, see if there is a Road Scholar tour near your home that you can drive to without much problem. Some of the shorter ones are very reasonable and you can see if this will work for you. I've done 5 Road Scholar ones in the US and had a wonderful time. One was a hiking program, 2 were birding programs and 2 were genealogy programs.
I hope you find something that suits your needs!