Well this is my point of view, feel free to destroy it.
Melka is one of the most survival characters, 3 ways to escape: claw lunge, spike, air stall, her down side a crappy sprint speed but a nice quick meele to dodge some bullets.
Thats why they recuded her hp, to allow players to kill her faster, before she could run and heal. This indirectly screwed her meele concept. She has the worst meele range of all, but she has high movility to compensate.
Her venom time got reduced because it was unfair to have a character who could negate sentry shield for 13 seconds at lvl1. This nerf/buff screwed even more her meele concept.
Meele tactic got hit hard two times, the only way to compensate would be increase her meele, to reward the risk; but does she risk that much with 3 ways to escape? I think thats why they left it that way.
Untill now, they wanted to try to buff her meele, but with poison doing and a “high” dmg, her dmg dealt would increase a lot, thats why the first venom nerf we recently had. The second buff that was a hard nerf to her poison, was a way to allow players to try to poison a target, reload, meele, retreat while you shot.
This shaked the only decent helix path, melka dosent rly have a good synergi btw her skills, helix and meele concept. She has this huge spread on her pistol and low hp, her poisom gave her the extra dmg she missed from everything else.
Her meele hybrid style is something they cant change, is in her concept, who she is. But they could give a versatil/utility answear.
A) change her helix in two ways, bullets or her monster arm. This requires a lot of work and an update.
B) give her a new tool when meele, a 1 silence every 4 hits, a wound, a slow, a stun after a full combo, etc.