I think anything over 80% is way too much (from what I remember when I used to go over my stats). SB looks fine but looks as though you're folding a little too much on the BB. What does your fold to steal in the BB against the SB look like?

Its a somewhat more complex thing to look at than just your overall FvStl percentage. I think you have to look at it on more of a position vs position basis. Also, you have to remember, besides BvB, defense vs steals is a combined effort.

I think you need to look at the steal from the perspective of the person stealing first. If someone from either the CO, BU or SB is stealing they need the people behind them to fold a certain amount of the time for them to be in auto profit, meaning, at that point, they could open with any two cards and it wouldn't matter what happened they would be profiting long term versus those villains by doing so.

If the BU opens for 2bb he needs the blinds to fold a combined 57.14% of the time to be in autoprofit (2/2+1.5). I employ a SB 3bet or fold strategy, so I don't cold call anything in the small blind and I 3bet about 16.5% of the time, meaning, from the SB, I Fold vs a BU Steal 84.5%. So if you were in the BB on my SB you would have to be defending about 32.5% of the time or folding less than 67.5% of the time to prevent the BU from being in auto profit.

BvB is easier to figure out because you are the only one defending. So its up to you to prevent the SB from auto profiting. If SB opens for 3bb, then he is risking 2.5bb to win the 1.5bb of dead money. 2.5/2.5+1.5=62.5%. So essentially if you are folding more than 62.5% of the time BvB, then SB can open ATC.

A CO steal gets more complicated cuz 3 people are defending.

I don't really know what solid numbers are from the SB but would think that most people fold around 75%-80% of the time, so your SB number is probably pretty good. From the SB you have an inherent disadvantage because you will always be OOP post flop, so I think you need to choose hands to defend that are +EV for you and not worry as much about whether or not you are being exploited by the CO and BU. Depending on what stakes you play, I doubt there are very many people considering this stuff. In addition, it is as much the responsibility of the BB as it is for you in the SB to defend vs Steals.

Like Harvie said, I think your BB FvStl is probably slightly high. From a pot odds perspective you can be defending pretty wide from the BB. For example, a complete trash hand like 32o has ~30% EQ vs a 50% RFI from the BU. The pot odds you are getting in that spot are 22.22%, assuming the SB folds. So in theory, if the BU is opening ~50%, you are getting odds to defend 100% of your range. That's in theory! I wouldn't recommend doing that, but just using it to illustrate that you are getting a really good price to defend your BB and you can probably be calling and 3betting much wider than you are, to a point that the minimum defense frequency is irrelevant.

Hope some of that helps and didn't confuse things too much

I really appreciate your detailed response, a lot to digest, but very valuable indeed!