First, this is NOT too much deliberation. You have to be happy with what you get, and you should make every effort to order what you want.
Sadly, my recommendation would have been the v3's, since I greatly prefer those over the v2's and v4's, mostly for the choke points. However, since that's not currently an option, I would pick the v4. As for why:
I'm 5'10" and am aiming for total length to be around 72"-76" (unless 76" is too long, I have no idea). I'll definitely start off with 32" inch blades and custom order shorter ones if those are too long.
Personal opinion, 76" is going to be too long. 72" is pushing it in my view, but you can probably make it work. Remember you lose about 2" of blade length into the saber emitter, so a 32" blade is really only 30" of "blade." I agree with starting with 32" and seeing how it works from there. What you can try is to get a piece of PVC pipe cut to 72" (or 76" if you want to try it), put some tape on it to delineate the hilts from the blades, and see how it spins. If you hit the ground with it, cut it shorter and try again. I'm guessing somewhere between 70-72" is going to work for you.
My main concern with the V2 is that there doesn’t seem to be much room at the bottom for a nice grip when using each individually. The raised part with the switch looks to be too close to the bottom which might get in the way... my hands are about average width at 3.5 inches (excluding the thumb) so I might rub against it which would probably get annoying. At 8.75 inches, there isn’t a whole lot of extra space for my hand.
If I understand what you're saying correctly, you're worried the bottom of your hand will rub against the raised ring where the switch is, yes? In my experience, it's not raised enough to be a problem. But what doesn't bother me may bother you. (I did just measure and my hands are actually about the same size as yours). I also tend to hold my sabers as far up the hilt as possible, almost to the edge of the emitter. Which means on the v4, I actually hold it in the curved "choke" on the emitter (if I were holding a version with windows, my hand would cover the windows). And I find that to be REALLY comfortable too. The v4 can be held lower, below that area, but I find it works really well for me to hold it higher.
However, I really want a staff where there’s just enough room for one or both hands and the blades and hilt are proportionate to each other. What I mean is it looks pretty weird when the total hilt length is pretty close to being the same length as one of the blades. In my opinion, it just looks better when the blades are noticeably longer. So getting the V2 might mean that there isn’t much room for my hand in dual wielding, but the V4s might look less proportionate to 32” blades. I’m not sure you guys tell me XD
The v4's look perfectly fine with 32" blades separately, or as a double bladed saber. That's how I have mine and they work great, split or together (although actually I prefer longer hilts for single hand use).
I know from the V2 and V4 aren’t much different in size (the V4 is only about an inch longer), but the photos on the website make the V4 look much longer and wider for some reason (especially in pictures where they’re combined). Even so, combined, that’s still a two inch jump in length so I don’t know if that makes a difference in spinning.
Yes, because it can make a difference in balance, depending on blade length. That said, the length and width difference aren't that much if you have each saber in front of you. So ignore the pictures and focus on the actual measurements.
Also, is the width difference between the V2 and the V4 noticeable and does it make any difference when spinning? (The V2 is 1.25” wide and the V4 is a standard 1.45” wide.) Choke points would be nice... but since that's not possible, does the size difference help grip and maneuverability or is it too small for average/largish sized hands?
It's not as noticeable as you'd think, but it's more noticeable than you'd expect. I find the v4 width to be perfect for me, with the v2 width feeling too thin. But again, that's just my personal preference. One way you can actually see the difference before ordering is to go to the hardware or craft store, find the dowel rods, and see what the difference feels like between a 1.25" diameter and a 1.5" diameter (because they won't have a 1.45", although the diameter measurements of the dowels aren't exact anyway). That will give you an idea of what each feels like.
Sorry if this seems like too much deliberation over such minor details, but this is the only lightsaber purchase I want to make for a while so I want to get it just right
Like I said, comfort of saber in hand is not a minor detail. Getting it right is important.
Question: Are you planning on getting sound? If so, that makes the decision for you, since the v2's cannot have sound.
Suggestions:
1) If you're not already planning on it, get the quick disconnect coupler option. It has several advantages over the standard or adjustable couplers in that it disconnect quickly (hence the name) and each part also doubles as a saber pommel, which means you don't have to worry about taking them off, putting the normal pommels on, figuring out where the normal pommels are, hoping you remembered to bring the normal pommels with you, etc.
2) I don't know how long the v3's are going to be out of stock, but I would be very tempted to wait until they're back before making your purchase. This particular sale/giveaway usually happens at least twice a year, so even if you don't take advantage of it now, it will probably be back again. US always has some kind of sale going, whether it's % off, giveaway, or raffle. And I REALLY prefer the v3's, because of the choke points, over the v2's or v4's (or v5's for that matter).
3) Have you considered the Apprentice sabers? They're pretty much the same size as the Initiate v4's, just a slightly different design, and the upper choke area on those is also very comfortable to use single handed. Plus it makes a great "stop" when using it as a double bladed saber so you know when your hand it getting close to the blade. They also work well with 32" blades.
Finally, I'm going to be "that forum person"
that points out that it's not really a staff, it's a double bladed saber. US does sell the Yari extentions that you can use to make a staff or even a spear for that matter, which are also spinnable should you desire.
Hope all that helped, feel free to ask any more questions you have.