Just my 2 cents.

- Bugs: it's f***ing annoying to always fly outside the track
- Soundtrack: not a single music I like, no style. Should have been a mix of W2097 and W3
- Hit detection: I hate to spin around 180° and then stop when I just brush one of those barrier posts
- Stupid ship design. Feisar is always good, maybe just a bit too short. Van Uber is ridiculous, Auricom the same, Tigron looks like a torpedo, Xios is a weird box. They don't look cool anymore. I thought in the future they had cool and streamlined ships with wings, but no.
- No "spirit": WoF lost all the spirit of the series. It just doesn't look cool, menus are ugly, music menu is dull, and the pilot faces are too stupid. I thought that (like the ships) Wipeout pilots looked cool, not superdeformed comic characters Comeon, Roberto Sergio looks nice but probably is good for another game. I want realistic faces, not these
Wipeout 2097 was flashy and cool with pumped soundtrack, Wip3out was somewhat more "sad" with dull colors and weird tracks like Xpander. Fusion is...what? Somewhat comic? Not an understandable style IMHO.
- Ship upgrades: whats the point of upgrading the ships? The CPU gets better in proportion, so nothing really changes, but still Wipeout has always been about pro and cons. I don't want to upgrade the ships, that's why I still have all the money and the ships are still the same as default. And also as I said it's no more about pro and cons, compare the stats from Feisar and Piranha...that makes all unbalanced
- Stupid challenges: survival challenges are so stupid and easy that make me sad, and I wonder why they put them in
- Bad variety of circuits: I wish there were more circuits, maybe from older episodes and less variations of them, too many alternatives of the same tracks.
- Too many weapons: I liked Wip3out because of the strange idea of making very few attacking weapons. IMHO it made the game less of a war and more difficult to catch the opponents. In WoF there are many stupid weapons, too many...and useless. Flamethrower? Protonic cannon? Supermissles? Biotrap? Bah....
Weapons like the gravstinger and gravity bomb (as someone else said) just ruin the game and the feeling of speed.
- No choice of class: many leagues, difficult raises, but classes were better IMHO.
- No checkpoints: less thrill, less adrenalin pump
- Too easy: I beat the game so easily, compared to how much time it took me to beat 2097 and W3.