A fully trained sense power for defence results in two times two difficulty upgrades, not increases (so no 2 difficulty dice added before purples has been turned into reds), to hit the force sensitive exile - if you're following beta updates, which we should. Additionally the force sensitive exile can, having invested lots of xp in the exile talent tree, add 1 to both ranged and melee defence (which I'd say doesn't turn it into a "general defence" or makes it stack with armour) - which results in 1 setback die derived from this talent tree against incoming attacks, be it melee or ranged - but not 2, as they don't apply against the same conditions.
So that's two upgrades - against two attacks (a third attack will only have to deal with +1 setback die from one of those two talents, plus potential armour) - that either turn an average to purples into two reds, or an easy in to one red and one purple, or a hard in to two red and one purple. Where do you get the three difficulty dice from? I may have overlooked something, but I honestly wonder as I can see nowhere on the force sensitive exile talent tree or the sense force power which support your numbers. Unless you're also referring to one or all of Away's different trees… then your math may be right, I can't be bothered to check just now.
Get the armour with the best available defence rating (1 - or 2 if you pick the personal deflector shield with no soak) - and lets say talents and armour stack when it comes to defence (they don't: page 134 beta book, middle of the page) - you're still "only" on 1 or 2 (depending on armour or shield) or 3 (if you want it to stack, and went for the shiled) defence/setback dice, before any dodge/side-step/defensive stance/cover enters into the equation. Granted this isn't bad per se, its perhaps better than other careers/talent trees where these defence bonuses grant upgrades, not setback dice to defence, and cost strain and/or manoeuvre… still, as is the difference is present, but I've still to feel the unbalancing or uneven distribution of power and beard in the group - granted the only force sensitive is female human, no beard (yet).
As for the talents trees in general, I like them, not sure I'd use them in my EotE campaign, but if I decided to do a test run of the KOTOR era or Legacy era I might pick these up - I have players who'd like to play Jedi, I think, not sure, particular if I set a game in the kotor-era…
The focus on damage and combat - well. In some eras the Jedi were more warriors than monks and hippys, like the war that culminated in the events surrouding the battles of ruusan for instance. Those jedi were more war and damage focused than, say, pre episode 1 jedi. Of course, making specific specs for specific eras could, I'd say would, be a waste of effort. What is "essential" Jedi? The force, harmony, knowledge, peace and lightsaber - more or less in that order. That means, in my opinion, that a jedi talent tree, or three if deciding on these kotor-roles that has cemented itself in the community that you would need some social skills, some knowledge skills, "mental" skills -as in cool, vigilance, discipline and the like - and one combat skill only, the lightsaber.
For talents, I think Away's done a good job through the revisions - I haven't seen what Dono's up to yet - I may not agree on all the stuff, I mean, I might have limited the Lightsaber Master talent to once per encounter, but hey… I'm not hating it the way it is the talent trees are all right, perhaps some more re-use of the force exile tree for defence could be added to, for instance the sentinel tree, but meh.