That extra "mechanic" is the one that offers power for sacrifice. But really what you are saying is precisely what JandK pointed out...you want access to the power upgrades of the evil path without sacrifice and consequence.
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No, I simply want both good and evil playthroughs to have the SAME mechanics, or at the very least, equal weighted mechanics/systems. If one system is purely designed to tempt players into a specific playstyle, but there is no alternate mechanic that balances it out, that goes against the idea of choice.
Exactly my point...you want equal power for zero sacrifice. But no...the extra power of the evil path is balanced for a solo playstyle where you end up alone or with fewer companions at best. You can't have that AND still have full party and other allies who come help you in the big battle. THAT is the entire point of the temptation and sacrifice...the extra party members and additional allies ARE your "mechanic". But that's not what you want. You want easy choices, you want a complete lack of temptation. You want to never have to feel like pressing the "do gud" button over and over might actually cost you something.
The thing I don't want the "Do Gud" button to cost me is invested play time engaging the game. I want to separate out the Dark Urge for the moment because if that path does indeed end up costing you all or the vast majority of your companions that's definitely a valid trade-off for taking the good path. Especially if the presence of companions opens up late game content that you can't have if you don't keep them in your party or on your side. Instead I'm wanting to look at the non-Dark Urge evil path.
Unfortunately, there's a lot we don't know and the biggest thing we do know right now on this subject has to do with a character who has been completely rewritten so it may or may not apply to the final game. We already know that Minthara and Halsin are mutually exclusive companions, you have to be able to kill one in order to recruit the other. Getting Minthara requires what's normally considered the evil path, and getting Halsin the good path. Obviously, this is the kind of thing I'm fine with. Good gets Halsin content, evil gets Minthara content--neither option is penalized. What is interesting is that in the EA build, taking the evil path also costs you Wyll. While I think it's extremely odd that the willing torturer is the only character who completely refuses to go along with the goblin side, that's a good example of what I think you're talking about.
If choosing evil locks you out of content that you would otherwise have access to by virtue of having Wyll in the group I'm fine with that as an alternative to greater personal power. If, however, there's a good choice further down the game path that locks you out of Astarion's content and they are the only two characters you can lose due to making good vs evil choices then I wouldn't be fine with it because that would mean paying a greater price in engaging content for playing good characters than evil ones.
All of this does of course hinge on the idea that keeping more companions provides more of a benefit than just getting more camp dialogues where you listen to Gale's condescending stories of how great he is and how you should revel in his smugness, basking in the light of his pomposity. What I would really like would be if "redeeming" Shadowheart (as an example) gave her access to certain abilities or even knowledge that was only possible if you took the "good" path. They don't even have to be more powerful than her normal abilities, just different.
I simply want the game to give me an equally rich experience playing good as it does playing evil. If that's the case, I'm fine with it and gaining more benefits from companions is a perfectly valid mechanism to do that. I just haven't seen anything except the Wyll desertion (which may not be in the final game as we don't know anything about the rewrite) to indicate that they have actually carried through with that. If they have, I will have no complaints on that level. Unfortunately, the way evil has been hyped up lately I'm not sure if they have actually done that.
