as someone with 3 sorcs, there are a lot of mechanics in the game that conspire to defeat the versatility of a wizard.
for crowd control:
sorcs don't have the slots to carry much in the way of crowd control, so spells such as solid fog were always a big conundrum for a sorc (do i scroll sf or stoneskin). most of us just scrolled them so removing them from the vendors would have been a fairly crippling move. however, not only did they remove them but the nerfed the **** out of their duration making them pretty much useless in most player's eyes. heck, it often took 5 repeats of the words 'fight in the fog guys' before the nerf to actually get people to do it, now the fog is gone before the 3rd statement.
for utility:
it isn't a secret that 4th level spells are an absolute crunch on sorcs so the choice between stoneskin, pk, solid fog, ddoor, firewall, fear, and enervate used to be a 'okay, which do i scroll'. taking ddoor out of the brokers has forced most of us to take it as a spell as the scrolls drop about as a rarely as a vorpal. once again, nerfing the duration of solid fog made it an easy choice of spells to drop instead of making me sit at the sorc trainer for an hour figuring out which spell i could do without.
for direct damage:
what kills wizzy versatility here is that in order to be effective against mobs you need to invest a ton of points into a damage line. most sorcs skate by this with fire/ice and disintegrate for everything else.
in general:
to me, the thing that absolutely kills wizzies overall is the ddo method of handling spell resistance. the extra wizzie feats really mean nothing when sorcs are able to bypass spell resistance with brute force instead of having to waste feats/enhancements on spell penetration instead of metamagics.
another fact that kills them is how bad the summoned pets are. holy ****, they are bad.
some thoughts for making wizzies more versatile:
double the current time on the lingering spells so that solid fog and the like become a valid spell choice again. this will bring back crowd control into the game and once again give spell swappers a choice. yank all of the lingering spells out of the brokers and wizzies become important.
change the wizzy damage enhancement lines (not the critical lines)
so instead of wizard fire/ice 1 through 4
wizard fire/ice 1 (2 aps) for 20%
wizard fire/ice 2 (4 aps) for 40%
this would allow them to spread more damage across more lines and allows for swappage to make sense from a damage perspective