That's interesting.
Whilst i don't purport to have the 'perfect' arena ratio's, I think its certainly better than the standard 15k,5k,500,50.
In the 3 season I've made it to DIV I in my country I've finished with 3,6 and 0 (Current) wins. But, finished 3rd, 2nd and 4th (current) in regular season gate receipts.
In DIV II, since I've had the arena with higher LT seating, i've always finished 1st.
I'm not sure why your friend with 10k, 10k, couldn't make it work.