i've seen both hax and s2j do a short hop to kinda gauge what option a person does to tech the platform, and if they don't tech, the falcon does a DJ nair to punish. for some reason or another, it seems like most people DI the nair kinda up because from what I can tell it usually leads to a knee
uair is not bad for non-commital platform stuff, but against good players it can be hard to actually land one. i usually go for one if i wanna cover the platform -> slip-off option (where they don't even tech and just slip off the platform entirely).
s2j also taught me about SH knee to cover lower platform techchases. SH knee under the low platforms of YS, BS, FoD (at the right height), and PS and it can hit the person above while still remaining a solid not-commitment-heavy option. Also, timing-wise, I feel like you could react to almost every tech option with it, so that would be good to play around with.
wenbobular also talked about covering multiple options with a moving full-hop stomp that goes over a whole platform.
worse comes to worse, you can go for a hard read with dair or knee if you're confident in the read. i think if you time it right, you can cover missed tech and tech-in-place while still having time to regrab a tech-roll.