Another shout for John Barth - outstanding writer who’s roughly a contemporary of Pynchon, but with a very contrasting style. Doesn’t look to show his arse as much, but the fireworks are still there.
John Crowley is another big dog in this area, although maybe lacks the heavyweight literary rep of other names as his work was ghettoised by the fantasy label for ages. *Little Big * is his masterpiece, from the early 80s - he’s quite different to Barth (IMHO) but shares a supremely controlled and gentle touch to this type of writing.
I don’t know if the OP or other posters are specifically focusing on experimental novels by male writers, along the lines of the OP’s list, but if not, there’s quite a bit of interesting experimental fiction by female writers including Virginia Woolf, Dorothy Richardson, and Djuna Barnes.
I really didn’t like The Magus, but I love the same author’s The French Lieutenant’s Woman, which would fit the OP (as well as The Collector, which doesn’t).
Wilson’s Schrödinger’s Cat Trilogy is even more appropriate. The three volumes all tell parts of the same story with the same characters, but can be read in any order.
My recommendation is JORGE LUIS BORGES. He writes short (often very short) stories, not novels, but they are the epitome of complex, experimental, and meta. If you like this genre he is an absolute must. His Collected Fictions is quite good, and comprehensive. The collection Fictions is, IMO, the best to start with (it’s a subsection of Collected Fictions, and also published separately).
Also, I third Cloud Atlas. Mitchell’s earlier novel Ghostwritten is also excellent.