I still have a few quarrels with the melee rules, but on the whole, they're a definite improvement over the Mutant Year Zero ones, and those were good already!
For one thing, a much more sensible
defense mechanism is in place. In MYZ, it's "
you're being attacked. Would you like to stand there without defending so that you get to attack next turn?". It's much better in Coriolis, there's more strategy involved. Move and attack (3 AP) in hopes to have the enemy down with the first strike, not being able to defend later in the turn? Move and quick attack with a knife (2 AP), even though the enemy's defense roll could be stronger than your attack roll? Lower initiative so the enemy gets to strike first?
Also in MYZ, the
critical injury roll always comes when your "Hit Points" reach zero, but never before. That makes battles much less epic, as PCs never carry on after an injury! Coriolis has wiped that flaw off the table, though I'm a bit disappointed that they're not temp reducing any attributes ever. There are some very gruesome critical injury results that I may have to change so that not too many player characters just die, lose the function of a limb entirely ... and players don't get reminded of similar ugly shit that happened in their family. Yup, the older you get, the more you have to reckon with real life trauma that the "cool and edgy" results in an RPG may in fact trigger.

Nothing a few house rules couldn't fix, thumbs up on the whole!
The
rules for initiative have been streamlined into an even simpler version, and I like it. All those sci-fi RPGs where reaction time really is the only relevant thing, where reflex boosters enable several actions a turn, making these players effectively fight action scenes alone and hog the entire GM for a half hour. And here's the kicker: I hear the old Coriolis version from 2008 was a pretty brutal offender in that respect. But no more!
Things that still irk me in the Combat rules
- Spend Darkness Points to have NPC defending? Oh come on. I understand why it was done, PCs in a heroic setting should/must have a decisive advantage over opponents to make it through the day. But this system way overpowers e.g. three quick light weapon jabs at the enemy.
- "Disarm" is too easy (a single additional six), the attempt always succeeds and it's a nightmare for the GM to describe in ranged combat. I can't use the rules like that. I'd have a never ending cascade of diverse weapons being slapped and shot (!!) out of enemies' hands. I'd rather this happened once every four fights, actually. Even in most stereotypical and boring action movies, it happens once per two hours.

- I'm not sure if I'm OK with the "grapple" rules. It basically makes opponents defenseless without a defense roll of any kind, which irks me, but then again, attackers can't use their precious melee weapons while grappling, so they have a choice to make.