A short lesson for TOs on how to handle regional pools:
Yes, it's true that 70 entrants is an awkward number to be splitting into 8 pools or 16 pools, but there is still no excuse for resorting to the worst solution possible, 12 pools. The solution here is to do 8 pools. There will be some unusually large pools of 9, but that's okay. Separate the pools into two waves. Assuming you have 16 setups (a reasonable number of setups to expect for a regional) let the first four pools play out from say 3-5pm on four TVs each, then let the last four pools play out from say 5-7pm on four TVs each.
Anyone who says this would take too long is wrong. Two hours is more than enough time to complete a 9-player pool. Do the math. 36 sets need to be played out, and you have four TVs per pool, so the amount of time it takes to complete the 36 sets is essentially the time it takes to complete 9 consecutive sets on one TV. Assuming a worst case scenario in which the average set takes ~12 mins to complete, that's still only 108 minutes, or 1 hour 48 minutes to complete one wave under a worst case scenario.
Congrats, you've now solved the problem of an awkward number of entrants while relieving the venue of crowd congestion (half the players can take their food break while the other wave takes place) and you've actually created the possibility of a balanced bracket!