You can make me reconsider, in fact, it would be quite easy for you to do so, just reduce the price increase to a 'reasonable' amount and still let me pay 6 monthly.
If you had increased your prices by 5-10%, then I would have grumbled a little, moved on, and would still be a loyal IPS customer. But this is a 48% price rise and you're removing Email support to boot. Sorry, that is a game changer for me, especially with all the other price rises I have from my hosting company and WHM/Cpanel recently.
So with that $220 saved, I can put that towards Xenforo, add another $50 and get access to Downloads and Gallery at the same time, and still pay less for my yearly subscription going forward. Sure my users will probably miss some features, but they will get used to them eventually.