Sorry to reply two pages late, but the way I understand it trying to play something like the USA will absolutely be going against the grain and be even more difficult in MEIOU than vanilla. So this is a bit of a weird argument.
I'm certainly looking forward to the mod update, but I think the team has way overhyped it. As well, M&T make design decisions that people don't like (I'm an avid fan of the series, and they almost had me never looking at the mod again with their terribly low state limit).
(TL;DR at the bottom)
It's not a weird argument, M&T isn't a blanket "make everything harder because of reasons"-mod. While the USA never became a world power in the timeframe it still went from being an unpopulated frontier to having several million inhabitants and growing fast, which cannot be modeled using vanilla-style development. Sure, the US won't be able to revolt for independence when it's just settled with a few thousand people, but that isn't exactly unreasonable. My point was about actually being able to become powerful later in the game. Of course if one as a colonizing nation focuses on settling the Americas instead of mostly dicking around in Europe one can get a populous USA far earlier than IRL. Basically we both simulate history better *and* allow for more dynamic fun.
As for your second statement that is harder to answer and even more so to answer briefly, but I'll try. I suspect that part of the reason why I am totally sold on M&T 2.0 is that I never really enjoyed pure conquest strategies for several reason, which is kind of an issue because there isn't a lot to do in vanilla (or even old M&T really) other than conquering stuff. Very limited internal politics, very little opportunity to actually develop your country (No, I refuse to consider Vanilla development as anything else than magically increasing arbitrary numbers) and just in general not a whole lot to do and strive for except for war and conquest.
While M&T 2.0 won't be perfect by any means (we have an ever growing list of stuff to be implemented post first release) I still think it's a long shot better than anything before it, simply because you can literally sit for hundreds of years barely fighting a war and still have stuff to do stuff, goals to set and reach and generally things to strive for and achieve. One of my favorite games is actually as more or less pacifist Hungary trying to turn the Balkans into a prosperous urban region (It's pretty shitty to start with). There's simply so much more to gameplay, and while most of the new content can be classified as "peacetime activities" it both lends new dynamics to war and doesn't necessarily make conquest harder.
And as for M&T making design decisions that "people don't like", that isn't exactly black and white. Many parts of the mod seems really terrible to outsiders that don't know that many things work very differently there. I could say completely out of context that provinces have a base unrest of 24 and that every province gets a modifier that mostly gives tons of monthly local autonomy. What that wouldn't capture is that it's all part of a system that basically makes remote lands harder to control but also gives autonomous provinces far less unrest to allow large empires without constant rebel whack-a-mole, while also making sure big nations aren't necessarily unstoppable behemoths if they don't make an effort to solidify control in their provinces (Like, say, building roads and stuff. Hello roman empire!).
But in the end me going on about this isn't going to change anyone's mind, so I'll just say this:
TL;DR: Try out M&T 2.0 when it releases and see if it's your cup of tea, it has far more stuff AND better performance than the current version of the mod!