I’ve listed below some possibilities and have link to a table showing what a “typical” progression would look like.
1) Easy1: UTF cannot be a Trained skill until achieving a level of Jedi Knight/Sith Apprentice. A pre-requisite for the Feat Skill Focus (UTF) is a level in Jedi Master/Sith Lord. This significantly lowers the UTF for lower-level Jedi characters, but has the same maximum as the books. The problem is there are large bumps upon attained the Prestige Classes (not necessarily bad, as getting trained and taking skill focus for other skills does the same thing).
2) Easy2: A pre-requisite for the Feat Skill Focus (UTF) is a level of Jedi Knigh/Sith Apprentice. Similar to Easy1, but not as drastic a measure. This is what we are using in our current Dawn of Defiance Campaign.
3) Feel1: UTF is not a skill. Rather, it is a special check that is available to characters with the Force Sensitive Feat. The check is = character level + Cha mod + 1 per force-user level (ie. Jedi, Jedi Knight, Sith Lord, etc.) This leads to an extremely high final UTF at the higher levels.
4) Feel2: Same as Feel1, but the progression is only +1/2 per force-user level. This lowerls the maximum as compared to Feel1, but still leads to high UTF at levels 15+
5) Feel3: Similar to Feel1 & Feel2, but the check is = 1/2 character level + Cha mod + 1 per force-user level. This keeps the skill mechanic of adding +1/2 per character level. The same difficulty with high UTF at levels 15+
6) Mike1: UTF is a skill, but change the Feat Skill Focus (UTF) bonus to be a maximum provided by the level-based skill bonus, with a maximum of +5 at level 10.
7) Mike2: As Mike1, but the Skill Focus (UTF) bonus is equal to the Cha mod.
8) Mike3: A combination of Mike1 and Mike2, where the Skill Focus (UTF) bonus is capped at the lower of the level-based skill bonus or Cha mod.
I’d be interested to hear about other suggestions. My favorite at this time is Feel3; partially because it gives a good progression and follows the skill mechanic. A +33 is very high for a 20th level force-user, but I am of the opinion that the game really starts to break down past 16th level, and I don’t plan on running games past that level. In addition, I don’t see that as being a complete negative, as I would expect an equivalently leveled gun-fighter to have ~+28 on to-hit rolls and defenses to be around the same.
Link to the table. The light blue is what I expect most optimized force-user UTF will be with core rules, and the light green is where the various optional rules meet the inflection point as compared to that light blue column.