That idea is already taken. There's available bitcointalk pricer which you can check the rank, posts quality check, potential activity and it's estimated price. https://www.bctalkaccountpricer.info
There's also another feature. The SMAS black list. The site will check if you are at list of banned from signature managers which are complied at SMAS. If you are determined to do your bitcointalk account estimator. Here https://bitcointalk.org/index.php?topic=1142314.0
They provide an algorithm for transparency basis. Good luck anyway.