Everyone has listed good options, but I would like to add my own ideas to the mix. In my experience, every bit helps.
Ram horns are a good idea, with some adjustment. Instead of facing backward and curving up and apart, have them face forward and curve inwards, to make them for feasible for weapon use. A rhino-like horn on the forehead could be a good option as well, if a bit unnatural looking, but hey that's okay right? (Seriously, when you picture people on all fours, it's clearly unnatural). If you like the horns idea, Estelle from Arknights may serve as inspiration.
Fangs and strong jaws not only fit the feline concept (jaguars are well known for their strong bites, which can crush turtle shells) but are dangerous weapons in their own right.
Claws are great for traction, but using them that way leaves them dull; this is why cheetahs rely on suffocating bites and sharp dewclaws to kill prey. Retractable claws, on the other hand, are kept sharp for when you need them. I would suggest having both traction claws, likely at the fingertips, and combat claws, perhaps positioned on the knuckles? It's up to you.
Roosters can be absolutely lethal with their spurs, so these are definitely a viable combat option. The best positions would probably be on the back of the ankle, the sides of the wrist, along the spinal column, protruding from the joints.....
You ever see a Thorny Devil? I don't know exactly how to add pictures, but a quick search (just a glance, really) should tell you what I mean by spikes. Those things are walking weapons, really. Combine that with uromastyx tail armor, except all over the body, and you will have people literally made for melee.
There's plenty of good reasons to add tails; they aid in balance, they stabilize maneuvers for more agile running (which is what cheetahs use theirs for, that's why their tails are so long) and they can act as weapons. Going off your feline preference, the tails in question would likely be slender but strong, think lean and whiplike. The end would likely have some sort of sting or "blade" at the end and/or spikes alongside the tip to increase its damage potential.
A stouter tail could act as a very good bludgeon, a long, prehensile tail could hold and wield its own weapon, grab and pull enemies, perhaps even throw objects. Prehensile tails aren't all that feasible for weapons usually, but you made it clear fantasy elements are involved in the OP.
Other great additions:
Sonic and Samus both demonstrate how great rolling can be as weapons go; considering these people are already spiky and possess armor, rolling could be both a means of transport and a very nasty attack.
Kangaroos are infamous for their 'double kick'; rearing back and using their tail for support, they lash out with both powerful legs. Jumping onto and/or kicking enemies with similarly powerful legs can be just as deadly; just ask ostriches or cassowaries.
C. Frenzy/psychological impact-
If designed according to this answer, your characters will naturally have high damage potential; making them have a 'blood rage' like mortally wounded bears would make them even more terrifying. People who can (and do) go on all fours, not to mention bite and claw people, are so obviously unnatural that just seeing them on the battlefield should incite terror and panic. People will likely claim they are demons with that alone, add in the blood rage and people will likely do everything to avoid a fight with them out of superstition and fear of their martial prowess.