To ruin or not to ruin

Hello everyone,
This will be my first post on the forums, although I do read throughout regularly because of my love for the E30.

I currently own a 1991 318is (purchased in 2012) and drove it through out my college years. The car needs TLC and I am through some other projects to where I can start planning and pursuing rebuilding/ restoring this one.
The more I read about particularly the 318is the more uncommon/ rare it seems to be. I am looking for advice and not here to beat on my chest about how cool my car is with it being uncommon etc.

What I initially wanted to do was cut it up, tube up front and rear + roll cage, and throw a 13b rotary or LS and have myself a drift missile; however, after the reading I've been doing, I cannot see myself ruining it if it is in-fact as uncommon as the evidence shows.

It is a 91 318is with black exterior as original paint, no sunroof, and black leather sport seats and of course has the 4 lug style 5s. I believe it does have the factory LSD option as well. The car is pretty rough but the chassis & body are solid. Interior will clean up well, and drivetrain is solid as far as I remember. Obviously will need to go through it all and make sure it is sorted out 100%. The original M42 is trashed but I picked up another one 2 days ago incase I decide to keep it closer to original.

I do not expect it to be worth all the money, or 100% Barrett Jackson type car, but for my own sake, I would like to know if this is the type of car that is best kept original. I can always hunt for another shell to use lol.

Any advice from those who keep track of production numbers and e30 gurus are welcome. I do not want to go beyond return with this vehicle if it is more special then not.

Thank you.