Inn to Inn Decision Fatigue-UK

The WHW is one of the nine UK long distance walks that we have done, and it's scenery and hiking, rather than castles and ruins. Most of our trips have been booked through Mickledore Travel, with whom we are entirely pleased. I suggest looking through the trips they offer to see if any appeal to your group.

I am not familiar with either Contours or Mac's. I recently did a 5 night trip with InnTravel on Lago Maggiore and was quite pleased. They worked with us to tailor our trip for our needs. So I would definitely consider talking to them about your interests. If you aren't too overwhelmed you might also look at HF Holidays, another UK-based hiking company. They do a number of hiking trips throughout the British Isles and you may find something that is more town/village-centric. https://www.hfholidays.co.uk/

You have 8 people going. That is a logistical problem right there just in numbers.
I can fully understand your feeling of being overwhelmed. It is easy to do. A simple trip is planned then you look at a map and suddenly there are a bunch of what ifs. You have additional input and desires of a whole group.
Seems you should focus on the WHW as a separate part of your vacation. Get it done and then you can do castles and such afterwards. This at least makes for a planning in sequence easier than incorporating too much on the trek itself.
I don’t know the mileage of your trip hiking per day, but to do 20k and repeat, and then tour around castles and towns the same day may be a stretch. Remember you have to get up the next day and move on.
We did Hadrians wall trek and we hiked without much sightseeing excepting Vindolanda. We did not stop and sit in quaint pubs along the way. Drinking beers is not the way to go if you have to get up and go another 5 miles. There is an A to B walk every day and that was the goal. Eight people will move slower than two.
We finished our trek, THEN we did the castles and other sites.

We have done three inn to inn tours with Hillwalk Tours - I highly recommend them! Last year we did the Fife Coast in Scotland and it was WONDERFUL. Loads of little fishing villages to stop in but also coastal walking with a variety of landscapes, incredible views, interesting explorations. There were castles we explored right along the path and doocots (look that one up), caves, historical sites, estuaries, amazing bridges, beaches, and wonderful towns.

It doesn't sound like the WHW is a fit for what you are looking for. You're right, you will not see much in the way of villages, castles, etc. along the WHW (or at least not the segments we hiked from Bridge of Orchy to Fort William). It has tremendous natural beauty, however, and lovely inns along the way.

I would also mention Hillwalk Tours. We used them and they were great. They have a number of options other than the WHW, but booking a long way ahead of time is probably a good idea (spots in the inns along the WHW for example were filling up 9 months out when we booked).

If you have a look at Mickledore Holidays you will find several other super long distance walking trails in Scotland which come far closer to meeting your criteria. And they don't do one of the other great Scottish trails- the Southern Upland Way- Scotland's coast to coast.

I hiked the WHW this past spring and the scenery is great but not much in the way of castles etc. I also walked the Dingle peninsula in Ireland and that had much more in the way of villages, ruins, etc. Lovely bnbs and scenery. I have used Hillwalks for both of those I believe.

The OP may be referring to Macs Adventure. If so, we went through it for a Camino de Santiago 5-day hike. We were completely pleased with it. I can’t speak for it with regard to Scotland other than to say it does offer hiking tours there.