casinos i have played at they either have the same amount of chairs as betting spots or less.. depends if is a 5 spot or 7 square table.. or if it is high stakes or not. I'm rarely playing at a table that crowded, so it isnt a issue for me.
I would recommend switching to two squares when the count is extremely positive IF there is three other players at the table or more to "hog" more of the high cards. When you get down to the last round in the shoe you can switch to two hands when the count is positive to get better penetration before the shuffle up... Also when you switch to two hands, it is recommended to bet 75% of your normal max bet.
