oh man this looks so awesome!
you were talking about working to make the combat/movement feel better, so i thought i'd put in my 2cents- this is an area where i have a lot of experience, and also an area where i see indie games so often not live up to their potential- just my personal thoughts though so obviously feel free to ignore
looking at your gif, there are incredibly easy cheap tricks you could use to get a stronger feeling of impact in your combat without adding new hit reaction animations or anything:
clear noticeable pushback on guy being hitit looks like you might be pushing him back a little when he is hit, but it is not enough to really feel the impact. the backwards force is either very slight, or it is being muddied by being mixed in with the force of his walking movement, or the falloff of the force doesn't have a sharp enough spike at the start to really feel it.
to feel more impact, i would cancel his walking movement for a short time (like 0.2 secs) when he gets hit and give him a significant enough force (in the opposite the attacker's facing) to see him pushed back at least a pixel or two instantly, probably more. That force would fall off on a curve like a reverse exponential or something, so the next update the push force is *0.5, then *0.5 again or whatever- so the curve has a very sharp spike at the start...
i don't know anything about the correct mathematical terms, but my animation curve would look like this
with force vs time
forwards movement for the attacker halting to give a feeling of collisionof course you may have perfectly good reasons for choosing to do something different here, but still i'll just say what i would to to get more impact.
I would push the attacker forwards with a little extra force as he swings. When he makes contact, i would either cancel his forwards movement, or give him a little shunt in the backwards direction, or both (depending on how big you intend the strike to feel).
for me this is very important so you feel when you hit. it doesn't have to be much movement to feel it, but then you have a clear feeling difference between making contact and swinging against the air
scale bounce on the guy being hit to substitute as a hit animationthis is such a useful trick for making impact feel on a budget. non-uniform scale can give things a bit of a bounce, and layers nicely over whatever animation you've already made.
the instant a guy gets hit i'd multiply his sprite scale (with center point at the base of his feet so he stays planted on the ground) X:1.2 and Y:0.9. the 0.1 seconds later i'd diminish the strength and invert the axis- eg. X:0.95 Y:1.1 to half the strength. then 0.2 seocnds later i'd diminish and invert again to X:1.05 Y:0.975, then 0.2 seconds later i'd return him to x:1 y:1
those numbers are very rough guesses, i'd try different strength and timing til you find what's right for your art
well that's my big rambling suggestion- don't feel like i'm bullying you to do things my way
i just like talking about this stuff and i really like moonman, and even though some or all of this might not be right for your game, it can't hurt to share what i think are some super easy tricks for getting more impact