Tips for an Intermediate Player (SF6)

I've been playing chun for a few months and have gotten her to a reasonable level (around 1400-1500mr) but I'm struggling to fully utilize some aspects of her kit and would like advice on some matchups.

1. how am I supposed to use 5lk? for 5f punishes I typically default to light legs for the increased range and knockdown, but I cant seem to find another use for 5lk. is it just for cashouts on these punishes or should I be using it as a counterpoke in some situations?

2. should I be using 5mk? I know that a lot of chun players use this button as an anti-air rather than tensho kicks, but the latter hasn't really given me any trouble and lets me react later anyway. are there situations where I should be opting for 5mk instead? right now it just kind of feels like a wasted button slot.

3. I'm struggling to use 5hk as an anti-air. I know there are angles where tensho whiffs and this will hit and you can get big damage off of it, but I seem to always react too late and eat a counter hit jump-in. is there any trick to using it? do you have any drills and setups to practice it?

4. alex is new and deeply evil. how do I stop this incestuous animal from crawling all over the floor? I know that the general counterplay for stomp is to neutral jump and punish with a jump-in, but chun's jump is so floaty and her primary jump in tools (j.mk, neutral j.hk) are so high-hitting that I struggle to punish it. should I be dashing out of the way and trying to whiff punish instead, or does it just require more practice?

5. another alex question: what button should I use to check him out of prowler stance? I know a lot of chun's strong buttons (5lp, 4/6mp) whiff while he's in stance, so I'm currently between 2mk and 2mp and wondering if any of you had advice for dealing with prowler.

any and all feedback is appreciated!!! thanks :)