I think Rogues should get Back-Stabber as a class special talent, and that Fighters should get Opportunist as a special class talent
Most of the listed talents needs some buff or re-do I agree.
However get noticed - The game rule set points to be classles. Same like Fallout. Rather then fixed archetypes offers (want to offer) freedom in character building. Therefore your propose to have some Talents locked to "class" is attacking the game's root. Do you think its good idea?
I can imagine a solution like:
Backstab - you can take the talent whenever you want as it is. + once you get skill level 3 in scoundrel you get it for free. The level 3 scoundrel should offer less skills (or less attractive skills)
Solution for talent for free at certain level skill should be more common for other talents too.
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The general idea for non-combat related talents:
All of these should offer a small bonus for combat, makes them viable to main hero and avoid to poison play like park Jahan at homestead and learn the craft&blacksmit only.
Examples:
Blacksmith - add bonus to armor equals to skill point Invested. So the level 5 blacksmith gives 15 points to armor.
Craft - add bonus 1 turn to length if food or flask for every level.
Escapist - chance to flee like now. + chance to avoid attack of opportunity +20%.
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The Elemental affinity skill
The elements are the cherry of the rule set. The skill should stay as it is. Maby add some spice on it.
--- Elemental shields gives the affinity bonus. Your whole body is covered by the element. You can hardly take better contact. Such change would make shields overpowered. So make shield more expensive, +3 AP generally. This makes shields favored by mages, but do not allow easy mod by spamming shields to every party memeber like now.