Well, I don't really know where to start looking for superchargers mod.

And I also know that supercharger doesn't have that "lag" because it's driven from the engine's crankshaft.
Turbos are fun because of that "lag" which makes you kinda stick to the chair hehe

This accord engine is K24 right? Maybe you can read this link:

https://www.torquecars.com/honda/k24-tuning.php

Just plonk in a K24A3......

I bought online & installed by myself.

For now I'd prefer upgrade intake side first (air / spark plug / fuel). Then exhaust side (manifold / piping / muffler). But also up to your personal preferences.

Yeah, IIRC - it's a K24A4..

I came across the same link too. But I'm not sure where to get it done haha. Still a newbie in modding cars, don't wanna kena potong, ya know..

What's the difference between K24A4 & K24A3? Isn't it all the same generally?

Must be skilled to install it yourself.. Envious of you. If it's possible, I would like to install it myself too, so don't have additional cost for workmanship hehe..

Air - You mean air intake? Open pod?
Spark Plug - I just changed mine
Fuel - What is this? Fuel Injector?

Exhaust side, I'll probably get it done once I rectify other issue.

Now for whatever reason, when I engage to D after letting the car sit for more than 8 hours, it will have some delay before engaging to D and the car will jerk. Not sure why is that.

Very Different. Go to the link a few posts up and you'll see.

Intake side upgrade that I mean is from performance air filter (OEM shape or change to open pod type) to throttle body (add-on any device or use widen size) to performance spark plug. But remind you that all upgrade will cost you bit higher FC than original standard config.

Just talk to my mechanic, his first basic recommended method is to add throttle controller like Works Engineering e-Drive 3.

Your gearbox already show failing symptom. Try to add ATF enhancement like JV Lube or Nano Estremo first & see if can recover.