Lady Gaga, as far as I know (from internet sources) is Sun in Aries, Ascendant in Virgo and Moon in Scorpio... So the Virgo ascendant calculation was most likely spot on, provided these sources hold any weight.
Personally though, I think it's a hard one to define purely on the basis of 'Lady Gaga wanting to perfect her image' since it's not uncommon to see women and MEN in showbiz becoming overly obsessed with personal appearance regardless of ascendant.
I imagine many other factors contribute in a chart to make a person 'obsessed' with altering parts of themselves to attain perfection for whatever reason.
I mean, look at Cameron Diaz for instance, as far as I know she is Libra ascendant, ruled by Venus, so there are strong factors associated with beauty but not so much the obsessive/critical qualities of Virgo, yet she too has had a lot work done!!
This to me could be 'perceived' to be just as obsessive as Lady Gaga, (different ascendants), I suspect with Cameron Diaz it is some emotional rejection of the aging process itself.
It is the driving force of our decisions that define us. The thought behind the action. And I believe this to be true for the accuracy of the ascendant when looking in from the outside.
I too am Aries Sun, Virgo ascendant and yes, I won't lie, I do have an unhealthy preoccupation with my physical appearance, however.. there is a but coming.. lol, I dress plainly, am not eccentric in way shape or form (mainly because I have no desire to stand out, in fact blending in is what I try to achieve), I don't like to wear make up except on RARE occasions and even then it will never be noticeable enough to 'stand out'.
I have a strong belief that first impressions are lasting ones and so I am more obsessed about how I 'appear' to others than anything else, as a protective mechanism I guess, and mainly because I am easily hurt by the judgement of others (something I am working on)
I do have the 'classic' youthful Mercurian appearance and therefore I go to extraordinary lengths to maintain it. I am not new to getting face peels, laser treatments (hair removal, waxing or other treatments), but does that really make me all that different to a non Virgo ascendant woman..?? I think not.
Honestly, it has taken me sometime to come to terms with my Virgo ascendant since it is not endowed with some of the more positive aspects of the other signs, it has however reinforced my belief that self-love and self-acceptance are an important part of the journey (if not the entire journey!) Realizing that we are all connected, smaller parts of a greater whole, as above so below.