That's true, some Pokemon would still be much more viable than others even if they were brought up to their evolution's stats. I will admit that my motivations for even bringing it up are pretty selfish -- I want to use Ducklett and still be viable to some degree without ever evolving him. However, if we want to stay true to the 'anime'/RP aspect of ASB, I think it'd be worth giving some kind of perks to people who choose to keep their 'mons NFE, in the name of using favorites.
This could also be interesting in the instance of Pokes that have drastically different evolutions compared to their starting forms, including things like Trapinch, Clamperl, and to a lesser extent, Scyther and Porygon2... to name a few examples.
For instance, I'll use the example of Trapinch, since I use one. It's saddled with a very high attack, low speed, rather average everything else, and an impressive array of Ground attacks to abuse. Granted Flygon can still obtain all of these moves, but in line with the roleplay, Trapinch is more adapted to use the vast majority of these than Flygon is. Additionally, the way you build their stats and natures is also quite a bit different. Personally, if my Trapinch wasn't going to evolve, I'd bulk it up and make it super bulky. Flygon is drastically different with its high Speed, wide Special movepool and other traits that make the stat-building process quite different. Supposing I opted to keep Trapinch Trapinch rather than evolving it... well, I think this is exactly the kind of point that Ducklett is trying to make.
On the note of Flygon... It's occurred to me, Flygon has the most well-developed wings and flight system of all the Levitating Pokemon (aside from Latios and Latias arguably, but in a way, they're not as maneuverable). Shouldn't Flygon be treated as an alternating Dragon/Ground // Dragon/Flying type, depending on whether or not it is airborne at any given point in time? Surely airborne Ground-types are not still immune to Electricity, due to the nature of the physics, and similarly, Flygon's wings should allow it to soar above the same Ground-type moves that Flying-types are immune to (but Levitators aren't). I'm sure there are other instances of things like this potentially happening, but what I'm getting at is... are special cases like this allowed and stuff?
Just some thoughts on all this. Let it be known that I am completely new to ASB (however I DID read all of the introductory and instructory posts at least once apiece) when taking these suggestions/questions/whatever into consideration, thanks.