At which point it's really no longer chess. Might as well just play Go -- humans can still easily outpace engines in taht game.
I beg to differ. I tried to play Go but I was beaten to death, while at Big Chess I had good results. It is just not the same game. I want to use what I have learned in chess rather than learning something completely different. I insist that Big Chess is still chess with the principles and tactical motifs being the same just you have no assistance in the form of theory or engines. You are in the wild and have to find out things for yourself.
Statements like this are odd to me. In standard chess there is a lot of theory in openings and endgames and huge databases of examples and books on strategy to help a person navigate the middle portions. It's as if people who make statements like the highlighted quote above are calling the work people put into learning and practicing this knowledge illegitimate.
You want to learn and explore a new chess-like game? Great. But you're still learning and exploring... this is no different from what some chess players have been doing for decades, working hard to expand and refine their skill.
If you want a large board, you could play taikyoku shogi (actually, good luck finding someone to play against): http://en.wikipedia.org/wiki/Taikyoku_shogi