Agree. I don't like the cap. However, while it disturbed me in the first phase of the game, i didn't care anymore from the mid to the end game as i just didn't know what to do with leaders (apart from the 3 in the government and 2-3 scientists).
I found the leader cap (unmodded) to be annoying from beginning to end:
In the early game, you don't have enough leader cap to have more than a couple Scientists. Given how the exploration phase is both one of the most crucial -- and most fun -- parts of Stellaris, it's a restriction that many players find baffling as it is frustrating.
And in the mid-game and late-game, you don't have enough leader cap for Admirals and (especially) Governors. Governors now apply their traits only the world they directly govern, with the remaining worlds in their sector only benefiting from their skill level now. So the game encourages you to place Governors on individual worlds again (like in older, prep2.0 versions of the game), whilst simultaneously restricting further than ever before the number of Governors you can actually have.
And let's not forget about the poor Generals: They were already underwhelming before, but at least you could afford to have 1-2, if only for the sake of flavor/roleplay. Now, though, leader slots are so damn precious, that you dare not hire any Generals ever, unless you're lucky enough to get one of the rare exceptions that doesn't count towards your leader cap (for whatever reason).
Don't get me wrong, I love most of the actual content in the Paragons DLC (yes, I do own it). But the "logic" that went into the design for the general leader overhaul (for both the main game plus Paragons) is simply brain-melting; it's almost as if the devs employed
1984-style "double-think" in their approach.
What do you do with the leaders now?
Scientists take up my "extra" leader slots in the early game. I focus on Governors in the mid-game, and then more on Admirals in the late-game. I only hire Generals if they won't count toward my leader cap (usually Marauder Generals or certain "special event" Generals).
The envoys are not on that list, aren't they?
Not at present, no. Stephen Muray does want to make Envoys a "normal" leader type like Governors, Admirals, etc., but he said that's for a future update.
Interesting
I should clarify/emphasize that Muray has said he hopes to make this happen, but it's not a done deal at this point.
Oh the other hand, it's been my experience thus far that if he's willing to state in a Stellaris dev diary that he wants to make "X change" in the game, then it usually ends up happening. So fingers crossed!
I just don't see the use of the new system, at least without the dlc itself, the new system is worse. But i am hesitant to pay for it right now.
Personally, I think you hit the nail on the head: The rework to the leader system is only worthwhile if you also own Galactic Paragons. And quite frankly, in hindsight, I don't think the devs should be rewarded for that -- not until they fix what they've broken.