Indeed, talents are very powerful and is a bit difficult to give advice without knowing which source books you're using. But i'll give it a try without talking about specific source books, let's first address your three suggestions properly:
+1 Talent at startup: This would make characters achieve some prerequisites for prestige classes faster (some of them do require specific talents) or allow a small "extra" amount of versatility to go along with getting the prerequisites for a prestige class (Usually if i decided to make a Jedi Knight, i'd be forced to restrict my talents towards that direction, so one extra talent at level 1 can alleviate these requirements a bit). Game impact from a GM's perspective should be small.
+1 Talent every level instead of every 2nd: Now this option really makes the game go to the UNLIMITED POWER!!! side of things. With it, your players can diversify a lot because they have double the amount of talents from level 1 to 20 (of course, that assumes the game will last till that point). This allows players to progress into some prestige classes faster than the usual or to diversify their talents, which will make class-choice impact even more (if you're playing with min-maxers, they will probably all gonna be multiclass jedi as this enables some very nasty combos).
One good example of the amount of power being given here is that with this many talents one can decide to master all Jedi Knight fighting styles (Shii-Cho, Ataru, Makashi, Soresu, Niman, Djen So, Juyo, Jar'kai) in addition to whatever he would build with a common character, so tread on the safe side here (you might get into a difficult position to create challenges for a game like this).
+1 talent at startup and +1 talent every level instead of every 2nd: Well, with this you get 21 talents. It's just a small step up from last one. It allows a relaxed start for versatility-players and a boosted start for specializing-players, it also couples this with a truckload of power possibilities. I'd name this game: Galen Marek is weak.
Now, all of this applies to players and npcs generated using the player rules (hence they balance each other out), but other creatures that are not usually created the same way as players will be totally out of scale if you're using your suggestions 2 and 3.
So i'd recommend using your first suggestion, the boost is noticeable from the player's perspective, but from the GM perspective it's just a slight extra and will probably not change challenge ratings much.
You could also implement a different suggestion:
One extra talent point at each tier of classes. Progression could go like this:
- First one at level 1
- Second one at level 7
- Third one at level 14
This follows the progression of classes that have 3 "steps" (like Jedi -> Jedi Knight -> Jedi Master). I see it as a compromise between your suggestions number 1 and 2 that does not give too much power.
Another good suggestion which is even contained in the source books is that between stories (read campaigns whenever they say this), you should allow the players to remake the character from 0 keeping levels, attributes and equipment. They use it to explain the evolution of Luke Skywalker's and Darth Vader's character sheets (which are different).
Well, that's it, i hope it helps a little.