Re: MMA=Mix Martial Aikido
I think at 2 years you qualify as "having your feet on the ground". I boxed, studied karate, collegiate wrestling, did some full-contact kick boxing and generally monkeyed around with other things before studying aikido. I think it all helped.
With respect to dealing with professional fighters, I think it's a pipe dream for 99.9% of those in any (emtpy hand) martial art to deal with them no matter how long they've been training. It's not the art, it's the artist.