My advice if you're planning a Wales trip...
Accommodation-wise there's no shortage of places to stay in Wales, just use Google/TripAdvisor. Only
you will know whether you want to camp on a budget or stay in a 5* spa hotel at several hundred pounds a night so anyone else giving you recommendations can be tricky.
For routes, Andy was instrumental in helping me plan when I organised previous year's Trophy weekenders, but I also put in a lot of time researching myself. Pistonheads has a sub-forum devoted to Roads (
https://www.pistonheads.com/gassing/forum.asp?h=0&f=45) and some people have posted their Welsh routes asking for advice, so it's worth scrolling back and looking into any posts that mention Wales - you might even find some of mine while you're at it.
In addition there's a thread which started off as a topic on the EVO triangle but has morphed and is a go-to resource for all things Wales (
https://www.pistonheads.com/gassing/topic.asp?h=0&f=45&t=304051).
Check out these in detail and start making notes.
Buy a decent road atlas, get a highlighter and start marking up potential routes. If you see a road that looks twisty and small then it's almost guaranteed to be worth a visit! Don't be afraid to go on the smallest classification of road either, they're sometimes the best.
You can approach it in one of two ways - either plan a route and stick to it, with a lot of driving all day, or give yourself plenty of time with a shorter route but allow yourself to have several runs over some of the best roads you find, some of which might be 10-15 mile sections. Whoever is planning the route, just take charge and plan the weekend how you want because if you keep asking for approvals each step of the way it'll never happen.