When we went with 3 people last month, we ended up with a handicap room. It had a HUGE deck!
We never went out there twice that we had the same number of "equipment". When we got on the ship, there were 2 tables, one large picnic type round table, plus the small table like on other verandas, and 5 chairs. Then, there were 2 chairs, then 3. I never got around to asking our cabin attendant, but it did bother me, coz SOMEONE had to haul that stuff through our room every day!
FYI, as far as I know, the handicap rooms all have a solid wall for the open veranda. I didn't like it as well, since if you were in a wheelchair, (and they all have wheel-in showers) you'd have to stand up to see over the wall. Doesn't make a lot of sense to me to have an open veranda where you can't see anything! In May, my mil has another one, and she's so short, she may never see the ocean!
Anyway, to get back to the point, you can definitely ask for another chair, but be prepared to be a little crowded. Thanks for letting me get that off my chest!!!

Kelli