The only thing being that if you roll something with a plan in mind you may not get as far as you expect and thus remain screwed until or even at level 50.

There have been rumors of immortals granting extra thief points as a reward, but Nepenthe has said on officials that this has never been in the case in the past.

Nepenthe is also very iffy about creating edges for thieves that will dump into extra thief points (similar to the 'extra train' edge).

There is a thief edge list under the Santa-zulg forum under long term projects that sorely needs attention if you expect to get any nifty edges within your thief's lifetime in any case, and it's quite possible that that thread will be what makes thieves as big a threat at hero as any assassin, voker or warrior.