For anyone that has run an extended campaign, how many talents did your PCs end up having by the end? PCs start with 3. The most any NPC I have seen has is 5. In Star Trek Adventures (STA) the starting is 4, and it seems significantly harder to actually improve your character in STA than in Dune. Does too many Talents potentially make the characters unwieldy?
Three should keep them going to start with.
But its your game, so if you want to run at a higher level or power or grant quicker advancement thats fine, it won’t break the game.