I think to add a bit more variety to melee there could be some use of the right mouse button. For certain weapons such as the fire axe, it could be turned round to use the spike, like when it was used with a charged attack in the broadway alpha video. The machete and kitchen knife could have stabs, and a stab with a kitchen knife through the face would be pretty damn fatal. The spade could use the side of the blade, which would be a bit more effective than the paddle slap. The claw hammer could use the claw etc. Also other weapons could use another side as a makeshift hammer, such as the side or back of the hatchet, or the back or bottom end of the crowbar. But, as a downside, it would barricade slower and occasionally slip on some hits.
Another suggestion is maybe some other models for some melee weapons could be added. The different model types wouldn't affect damage or hit speed but just have more variety than seeing several of the same crowbar or hatchet. There are various different machetes, barong machetes, bolo machetes, and those stylised ninja machetes. There are fibreglass handled hatchets and one piece steel handled hatchets, wood handled hatchets with the wedge friction instead of widened top friction... I could go on. Just a few different iterations of each model would be nice for immsersion into the game. I'm not expecting this as something that needs immediate integration, but just something that could be done over time, as the mod develops. Thanks for reading.