I had never heard of that Skyrim Perk Calculator before, but it looks very cool. The developer obviously put in a lot of effort to build it, and it seems that he's in the process of updating the site, so I'm interested to see what the new and improved version will look like.
To be honest, even if I could somehow negotiate a deal with the creator of the Perk Calculator whereby I could use his code on The Elder Stats to generate perk trees for characters, it would probably take away from the appeal of his site if The Elder Stats suddenly started offering that feature. I was once asked by someone making an Elder Scrolls site similar to The Elder Stats if I would be willing to freely give him a copy of the codebase for this site so that he could use it for his site, and that he would give me a small mention of some sort for having lent it to him. My response was an amiable yet firm "no" — why should I freely hand over my hard work to someone else who will use it to produce a service that will likely be in direct competition with my own? I feel that I would receive the same response from the creator of the Skyrim Perk Calculator, and I would respect and understand such a response being a web developer myself.
Now, I could implement my own version of a perk tree generator on The Elder Stats with some work, but I'm at the point now where I'm seriously questioning whether or not adding medium-to-large scale features to this site is really worth my time anymore. In the past year, I've become very busy with my undergraduate engineering studies, in addition to learning Android development and working on a new personal web project with a friend of mine, so my time has become increasingly more limited. I really love The Elder Stats, and I don't want to let it stagnate by becoming outdated or not providing enough new features to keep users interested; however, I haven't seen the activity levels on this site that I had expected to see for quite some time now, and thus I have questioned whether continuing to improve and add-on to the site is really a worthwhile investment of my time.
So, while I'd love to implement a perk tree system for character profiles, along with some other neat stuff that others have suggested in the past, I don't know whether I'll actually get to it, or whether there's even enough interest from the community for it to be worthwhile for me to do so.
I appreciate all new feature suggestions, though, and hope that one day I'll find a way to implement them here.