Good one but you need more things to do as there are also more competitors for you in this market. So develop more sharply and provide more services for clients.
I really cant find any lacking in your website. Infact what i did is i just copied the link of this forum page, pasted it in your site, got it short, opened in another window and now i am writing this reply in the same page that i opened from your site. your design is clean, simply direct to the point. i would suggest to slightly elaborate the words shorten links, my links etc that you are using on home page to make them more easily visible to the viewers while keeping its simplicity. as far as your domain is concerned i guess you decided srt as a short form of word (short). good work...