Alright. Here's some recommendations mostly based on what you've already read.
For tears, I don't really have much. One ~Kagayaku Kisetsu e~, made by pretty much the same guys who made Air and Kanon. It should be pretty similar, both in comedy department, and in fantasy drama department.
Narcisu, a true tearjerker in it's very definition. If that's exactly what you're looking for, then this novel has it for you.
For drama/romance, a category Key also excels at, there's a few more suggestions. Grisaia no Kajitsu, my go to recommendation for nearly every request. Lots of comedy and a long common route. Drama and Romance in all of the routes. Depending on how sensitive you are, you may cry on some occasions.
A Profile, which I'm not really sure of it's english name. A pretty average game, but it fits the category above, and I liked it.
If My Heart Had Wings. Other than a butchered translation, it is a rather good romance/drama.
Hoshizora no Memoria, a very dear Visual Novel to this forum (mostly due to a certain character). Another good romance/drama, with a lot of routes to play.
Finally, if you enjoyed Steins;Gate you might also enjoy the Muv-Luv Trilogy, disguised as two games. Muv-Luv, in particular the last game, has a lot of stuff. Really. So it can't be categorized into one genre only. It's adventure/action/sci-fi/drama/romance and whatever more you can think of. It's widely regarded as amazing, so give it a try if you feel like it.
I suppose Chaos;Head is by the same guys who made Steins;Gate, so you could try that, even though I think they're not similar at all.