How can I say that you are a pro gambler? You are stating by yourself on this:
For a couple of years, I had a lot of success betting on football from very obscure leagues. I had an algorithm which was great at spotting games where bookmakers had not priced up correctly.
What? I don't see any thing on that quote which supports your statement. OP mentioned that he became successful on sports betting and not on poker. Nah, nevermind.
He said:
For a couple of years, I had a lot of success betting on football from very obscure leagues
By saying that, I only think that he is a pro gambler because not many of us can get a lot of success betting on football

Perhaps, if he still stays with the betting on football and doesn't move to a poker game, he could get more money because he has much experience in that game. I only think that he wants to try with a new game and he choose a poker game.
But to be honest, the poker game is too difficult to learn as I try to learn, but I failed over and over, maybe it because I don't have interest in the poker game or maybe a poker game was really difficult.