I think the show needs to find it's legs first. Lorca could stay or go, it won't matter. The writers on this show are good writers, there are great ideas here and great creativity, and though I enjoyed the last two episodes I think they really need to start hitting the story they were trying to tell.
They need some more character development for me to even care as much about them coming or going. I like the characters but they don't seem well enough tied together for me personally yet. Within just a couple episodes of Daredevil or Jessica Jones or DS9 I found I had a good idea of the characters and what they were about, as well as an attachment not to them personally, but to who they were in the world they were in.
I don't quite have that with STD yet, perhaps I'm just too picky, but right now I can't say I'd care if Lorca stayed or went.
Stametsm Saru and Tilly are the only characters I have a real interest in. Michael, there is a great character there but I feel it being a bit squandered.
If Lorca were to leave the show, it'd be hella funny if Saru accompanied Lorca onto a Klingon ship against Saru's better judgment, and Lorca was killed by a Klingon despite Saru's best efforts.