I really enjoy Obscured by Clouds. It was written and recorded very quickly so it doesn't have the substance of Dark Side of the Moon or Meddle. But it does show the band working together and jamming very well together. A great collection of songs.

You didn't mention anything from Wish You Were Here, it's amazing, hopefully you already have it. If not, get it immediately.

I would also highly recommend some of the Early Years sets. 1970 and 1971 specifically. The live Atom Heart Mother without the orchestra is amazing. The BBC 1971 show is perfection from beginning to end.

A lot of people don't like it, but I actually really dig More. It's a bit uneven and an oddity in that it's a mesh of folk, a couple very hard rock songs, experimental soundscapes and a few random numbers. There's a couple clunkers, but when it's good, it's very good.

The live part of Ummagumma is really solid. I'm not as harsh on the studio album as other people. It's not really that accessible, but it does have some good moments. I like both intros to Sisyphus and Grand Viziers Garden Party (the middle parts can be tedious), Narrow Way part 1 especially and Grandchester Meadows.

Honestly, my favorite Floyd stuff is the live stuff. Especially up to and including 1972. All their subsequent tours are great, but they are more formulaic than the early shows. I definitely recommend checking those out.