Spiked knuckles and brass knuckles, tied to unarmed combat instead of cutting/bashing etc. combine them with a steak knife or combat knife to make a trench knife (essentially a pair of brass knucks with a knife welded to the inside grip so you can punch, block and stab quickly. Also I second leg armour. Ideas for this would be the soft/hard leg under armour, ballistic kneepads the like you see swat and the army use etc.
I can certainly see wearing 2 backpacks and 2 military rucksacks being encumbersome but at this moment if you want to melee it’s either armour and no storage or storage and find a suitable window-- and in all cases hope like hell nothing bites off your legs. So like jagi says cutting encumberance levels would help, or just allow stronger characters to get more volume out of their clothes (like the op says-- stronger characters generally would have a larger body build, so the suitable clothes they find would need to be larger than normal anyway. and yes, small people can be strong too, but if a stat level of 8 is average 14 str is pretty much world’s strongest man body-builder level.)
