A friend of mine who used to play a lot of 40K suggest that we give One Page Rules' Grimdark Future game a tryout in the summer, so that he can use some of his exquisitely painted armies. I haven't played 40K since the first edition, but the OPR rules look nice and streamlined: a bit of Song of Blades and Heroes (with the Quality stat); a bit FUBAR (with the alternating activations); and a bit Kings of War (the general streamlining): all good things, and the rules and list-builder are free to boot.
I was planning to paint up a lot of first-edition 40K space orks for the summer session, but I'm aware that time and work commitments may limit what I can do (and I don't want to rush those old treasures). But I have no qualms about speed-painting kitbashed EM4 plastic orcs (wonderfully cheap and readily convertible). I converted one to sci-fi a while back, along with an associated metal Nick Lund Grenadier orc, so I thought I'd convert a few more.
One welcome discovery has been that the new Frostgrave cultists have bulky arms and gloved hands that work nicely with the EM4 orc torsos. The arms (and chainsaw) of the figures in the first photo come from that kit. Stargrave scavenger arms and various other sci-fi bits make up the rest.
As far as I can see from the Grimdark Future rules, the orc profile is all about aggression rather than toughness (as in the original 40K, where T4 was an ork's main advantage). So these smaller, rather simian orcs should look the part so long as they're armed to the teeth.