I have my units at slightly under market rent, it lets me pick and choose who I want as tenants.  

Increase given today may not be in effect until Aug 1 meaning increase (if 30-day notice is applicable) would be effective Sept 1.My guess is that MA Winters start stalling market rentals in Oct which means you may be risking a very long vacancy window if either or both tenants choose to vacate. 

There are tons in SoCal to choose from. 

You or your spouse may even choose to become a real estate agent yourself to gain access to the incredible tools that agents have.

This market is almost as supply constrained as NYC and also almost as expensive, so I'm not sure what the advantage is for you to choose a business which is 5 hours driving distance from you...What made you start a fix and flip business so far away from your hometown?

Then choosing spots like these gentrifying areas are what turn triples/homers into grand slams if they pan out as expected..

I could sell people junk like this but choose not to as I know what happens long term.  

If you decide to go the leverage route, there is no good reason to choose the 15yr option... as @Brie Schmidt  said, you can always pay extra to put it on a 15 year schedule, but the added amount will not count against your debt-to-income ratios when you are ready to aquire additional properties.

Ideally, I want to choose the state that shows the most potential for both being an agent and for investing in real estate.

Otherwise I think you need to choose between being a renter with a voucher or a homeowner with no voucher.