I kind of agree that 5.e3 can be a smidge of a buzzkill, but I think there are a few buzzkillers in most of the options you mention if you assume really well prepared opponents that play perfectly, e.g. the Modern Main Line of the Benoni basically requires the ...b5 sac and then is not a ton of fun, the Bayonet or h3 lines in the KID can be a smidge one-sided, etc. Our tastes might differ of course.
The g6 lines don't necessarily look like inferior Benkos to me, but hybrids between the ...e6 lines and the ...g6 lines, which makes them a smidge confusing to conceptually unravel. They're very complicated, and both Avrukh and Kotronias/Ivanov invest a ton of time in showing they're playable and interesting. If I had to win this would be the route I'd go.
One line I have looked at a smidge and might be worth considering is
5.e3 e6!? and then:
6.dxe6 fxe6 7.Nc3 d5 8.Nf3 c4!? is not very popular but scores very well in the lichess DB. A few correspondence games have followed the line below and have tried different ways of untangling on move 18:
Not an amazing winning try for Black if White knows it all quite deeply but hey, you're Black.
6.Nc3 exd5 7.Nxd5 Bb7 8.Nxf6+ Qxf6 9.Nf3 Be7 10.Be2 O-O 11.O-O seems like a position that most Benko players, at least the ones with a disposition towards the usual ...e6 positions (this is not generally me), would enjoy.