You know, I've never actually considered your idea of keeping choices up after selecting them to emphasise them, but now that you mention it...yeah, that's actually a really good idea. (Though I'll definitely be going with option #1 of the suggestions you've made - the others sound a bit intimidating for me!)
Viewing post in How I tackle UI and Playability comments
To be clear though, I think everything I say above would be inappropriate in tech-themed games like Artificial Nexus (Or Coffeedrip Studio's Esper X Guide.) where the whole theme is that you're battling against an indifferent computer system. In those cases, it's thematically consistent that the player's entries are somewhat colder.
I'm also aware of examples in Noir where a serious decision 'pops up' in a way that feels inappropriately cheerful!!! Argh!
I suppose that all I mean by the post is that this whole area of screens entering/ leaving in RenPy is a design space that I really appreciate seeing people play with (Although I admit I might be crazy.)