Personally, if it were up to me I would give the Brewster and F4F a 5 minute WEP and reduce the MIL settings on the Spitfire Mk XIV and other aircraft with MIL settings based on short time limited settings.
That's fine as an opinion but like I've said before it would cause more problems than it would solve. Where do you draw the line on what is a "short time limited setting" and what is not? Allisons would get to run their 15mins indefinately because they have 5min WEP-limit above it?
HTC has clearly chosen to time-limit which are clearly called/considered emergency power by the manufacturer/service branch. One can disagree with that choice all they like, that alone won't change it in anyway though.
Anyway, there's one inconsistency to this that I've noticed compared to the B239/Spit14/F4F-4 and that is a P-39Q which can't run its 5min take-off limit indefinitely in AH. And before anyone starts, that is by definition an inconsistency not the rule. So, to make it consistent with the rest of the planeset its max. non-WEP setting should be raised from 44.5HGin/1125hp to 50.5HGin/1200hp.