I barely game on my phone at all. I think I only have one game on my phone and if I couldn't install it, I wouldn't miss it.
The only thing that I worry about as far as space is being to able to cache certain content such as content from Google Music. I don't think that Google Music can be configured to use a different path to store content other than /sdcard.
Or am I just worrying about things just to worry about things?