Yes, there is some balance, but warrior has burst skills remember? As I remember, even counting all that warrior has lots of weapons skills, engineer and elementalist have lots of weapon skills after taking into consideration the attunement and kits, and thief still has less variety. Mind you, that's fine imo because theif should be spending more time learning to move and shutdown, and less time learning to use weapon bars.
Seems to be that regardless of how many weapon skills each profession have, they all have pretty good options for dps AoE and single, for control, for shutdown, for support, etc. The main lacks I can see is that professions tend to either focus on support (guardian, ele, engineer) or shutdown (thief, mesmer). Or I might be wrong on that one.