You've seen my posts enough to know that I'm not a fan of sitting around waiting for results before studying for the next one…
HOWEVER…
I'll change my tune here. I think you should pick the 2 you're going to focus on first – let's say FAR and REG since that's the ones you're working on right now – and stick with those 2 till you pass one. Take one, then the other, then re-take the first, then re-take the second, etc., till you pass one. Don't add in a 3rd till you pass one of the first 2. FAR and REG aren't really 2 I'd pair, since it's combining GAAP and IRC, but everyone has different philosophies, so pick whichever 2 you think would be best and stick with them.
Also, if running out of time on an NTS is a recurring issue for you, then start getting 1 at a time on an NTS, then apply for the 2nd one's NTS when you're within 2 weeks of actually being ready to sit for the 1st one. I know, this is opposite of what you see me say on here most of the time, but I think it's more applicable to your situation.
I'd also suggest that you add, vary, and modify your study techniques constantly. One day read your book out-loud to yourself; the next day use a whiteboard (or papers taped together) to “teach” your cat or dog or your kids' dolls the principals of whatever you're studying; the next day come up with your own mnemonics; the next day watch lectures all day; and the next day get one of your kids to help you do MCQs as fill-in-the-blank (so they don't give you the answer choices, you have to come up with your own answers); etc. Doesn't have to be day-to-day, could be changing methods every hour, but focus on finding new and different ways to learn and mixing them all up. Don't go “OK, for this retake, I'm going to use the ‘pretend to teach to someone else' method for everything”, but use it in combination with everything else.
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