I used only the games I have played, and knew their character creation process, I have not played LOTR, so I have no idea how that game plays.
However, from what I was able to understand from what I have read around the forums is that DDO and LOTR have entirely different graphic foundations, which is why they have not made their graphic scheme similar.
I could be wrong on that, but that is what I gleaned when discussions on "Cosmetic" armor slot that LOTR has and DDO does not.
I was discussing with my wife a while back how doing something like that would truly revamp the game in the way of total awesomeness if our stats were reflected in our model as you put out, having the sliding bar linked to our stats.
There would need to be limits tho, that only "Natural" starting stats mattered, not magically augmented stats or even tomes would apply, just the base starting stats. Maybe IF they could do it, have it so that our level up stat applied as well.
However, as the case would be, Warforged would be exempt from this in many way as they are constructs, not flesh.
And yes, the burden that would put on the system requirements would also be an issue, and since I am playing with a borderline system, I can't say I am a fan of making the game even more graphically intense for me.
As it stands tho, right now, I would like to see at least a minor step taken to allow us to customize our characters. That can start with Warforged beling allowed to have a second boy option for Females that are different from males, if not just to make some players more willing to play them. but also to make it so less gender mistakes happen in the "creation forge".