I'd say its a pretty dumb idea;
you're attempting to enforce a standardised set of mod content- essentially demanding everyone be/like the same; which in turn will make individual modpacks less individual and unique.
Likewise consider the cultural effect; ideas such as this only gain momentum due to the mods in question being liked by the supporting crowd (or in this case people supporting this to stronghold their own opinions of Xmod).
If you were to try to apply these same mechanics to a less well liked mod then I can guarantee a significantly more hostile response from the FTB community.
Similarly people who may not enjoy using Ymod will feel the same way about you trying to force it on them.
[For my own tastes- I'm pretty fed up with turning off every HUD mod in existence every time I play a pack or update]
What you could possibly do is expand the master config; so theres a standardised set of controls/keybindings/remaining non-infinite IDs ect...
Or better -- design a keybinding-control mod for the FTB client; so one's personal controls can automatically transferred to a new pack.
I like those ideas, and I see where you're coming from. I don't doubt that I'd be walking a fine line, but what I would like to institute isn't a mod standard, but more of a code standard.
If done properly, I feel like having every working piece in a mechanism constructed and modified under one standard would function better. Better in respect to each piece made to an undetermined standard in which each piece needs to be adjusted until it functions, and not always optimally.
Now, if it were possible for one person to maintain said conglomerate, the next issue as mentioned is creativity. Will I simply rewrite everything someone else has ready made? Will I just plagiarize other ideas in the attempt at a grand idea, or will I attempt to venture off in my own direction, possibly failing to meet the excitement and diversity everyone endears?
Either way, the main idea isn't a super mod that forces someone to use Xmod. No, it would start as a core. Each and every mod would develop around that core, until only maintenance would be required. Now, instead of downloading 5 cores for 15 mods, say you wanted to play a magic map?
Aright, just download:
--Core, magicA, magicB, and magicC
as opposed to
-- CoreA, magicA and magicB, core B, magicC, D, E, etc.
If you want to at magic-tech, same thing. This isn't an idea to make a mod that forces people to play a certain way. Rather, it's an idea to make a mod that is so modular that could be played hundreds of ways.
Of course, the ethicality of this would have to be called into a question. If this is a success, what of the other modders? Will this mod became so useful that there is no need for other mods? I would hate to push another modder out of the community via the success of a silly bit of OCD. I think the intent is noble, but when ends meet, it seems to big, too bulky, and too unethical.