What is more I am Donk-Folding 54% with is too high because of my strong donk bet range. I have read that this should be between 25 and 40%.

Stop looking for perfect stats. Play situations. You should donk in situations where the flop supports your range and not your opponent(s) when you have a monster or can't profitably c/c but don't want to fold (gutshots, pair+overs w/bd draws, etc..).

Yeah I totally agree. Players at low and microstakes have such tremendous leaks that playing in a way the best players at highstakes would, is far from being the most profitable way. I'm not saying you should be playing totally unbalanced but in a lot of scenarios adapting to your opponents and the fields tendencies is gonna be far more profitable.

If people are paying off your strong donk bets and not picking up that you have a super strong donk betting range then I would just keep doing it instead of trying to balance. If some of the regs start folding to your donk bets constantly, then I would start incorporating bluffs against those players.
As far as your donk-fold being so high, not really sure what to make of it. If people have super nutted flop raising ranges and your donk-fold is just what % of the time you fold to a flop raise after donking, this might be fine? Assuming that since they are nutted you are only getting 2bet on the flop very infrequently so it shouldn't be hurting you much.

A common perspective on donking flops is that your hand must meet 2 criteria, 1) too weak to check/raise and 2) too strong to check/ fold ( Galfond, Forrester, Fitzgerald) The problem with this strategy is that your donking range is very vulnerable to raises
What happens on turn, and river is seldom discussed, but when the turn heavily favors your range Id be inclined to suggest that donking is preferable here because alot of players stop betting on turns that are bad for their range and then get to realize equity on river for free.

A common donk spot I found in live play is check/call flop HU with something like 44 on 378 and donk 40% psb on any turn 8 or lower, but thats live play and exploitable.

Another consideration is the cbet % of the pfr. If the pfr has a low cbet % you can donk alot of low boards.
There are so many combos of JTo+ and Axo+ that brick on 9 hi boards that donking can effectively deny equity to.
When I opened up with donk betting I noticed it often takes 2 barrels because people are more inclined to "call once" IP rather than OOP, so be prepared to fire on alot of turns.

When facing donk bets vs fish I like to do alot of floating drawing to a check from them on the turn, but these turn bets IP also get called more often by a weaker/ capped range so be prepared to fire rivers more.