It could be done, but I see a few problems with this plan...
- There is a risk that the hiring minimums you are planning on will not be available, ie you might need 1000/200 or something like that.
- You are probably focusing yourself on bottom-feeder regionals...some of the better regionals have higher mins. what if you get stuck there for 10-15 years?
- You are probably going to spend more money trying to rush, especially if you have to buy ME time.
- You might well have to buy all the ME time you need. MEI jobs usually go to more experienced instructors, because of common sense, insurance requirements, or a seniority system.
- The "1500 rule" is actually an "ATP Rule" and they might still lower the hours for SIC's to some compromise like 800. Also, quite frankly, if there is enough of an ENTRY-LEVEL pilot shortage due to the ATP rule, it will get thrown out real quick as regionals start stranding PAX due to lack of crews. Money talks, BS (ie safety) walks.
In the grand scheme of things it's not going to be worth it to try to beat the deadline. Try to keep a day-job while you train and pay-as-you-go without loading up on debt. You'll thank yourself later. A gainfully employed CFI can log 1000 hours in a year, so you're probably only looking at a extra year or maybe two. Not to mention that ME time, you have to figure out where and how to get that.