I think the Vespans are missing a thorax. The others are all good proxies IMO. The Swamp thingies are better fed than my Hlutrgu, I understand.
Good point! They do look a little 'cramped', at least from this angle. Yes, your Hlutrgu are better all round, I'd say - but these are fairly decent, I think.
I was idly musing over Tekumel in 1/72 during work breaks today. Before Covid, I was working up a set of 1/72 RPG miniatures for ease of transport (I was getting down to London with work now and then, and was meeting up with old friends for some gaming, so wanted ultra-portable miniatures. 1.72 based on coins and carried in magnetised boxes are ideal for that). I'd thought about both Glorantha and Tekumel in that scale, but hadn't really investigated the latter. I think it could work quite well - especially for humans. And of course it's dirt cheap.
Here are some possibilities from the Plastic Soldier Review website.
Tsolyani, etc. (Caesar Incas):



More of the same (Caesar Maya):



Yan Kor (Caesar Philistines - and note the Nluss bodyguard at the end!):



There would also be some potential for priests of Ksarul among that lot.
There are loads of options for Salarvyani. These are Caesar Assyrians:

Now, the non-humans present a bit of a problem at 1/72. But not, perhaps, an insurmountable one. Pygmy folk are easily created from 15mm ratmen and the like. And 15mm werewolves would work as Renyu. And I think there are a few "weird centaur" aliens kicking around that are big at that scale and might work just right in 1/72.
Also, for big creatures of variable size (Sro, Serudla, Hra, Thunru'u, etc), smaller 28mm types - like the 'trill' - might work as the bigger sorts at 1/72.