What am I going to do?

I'm currently writing More Than Enough, MTA #3. I'm almost done with the first part, which only covers about two weeks in the story itself. The first part wasn't supposed to be 30K long, but it's getting close to that threshold now, and it's likely going to tip over it. 

That means that I still have another two or three parts to write, and if they end up just as long, the book's going to be huge. So what I've been mulling over the last two days is to simply release the first part as it is and then write the other parts afterwards. Perhaps publish them individually as well, if they end up as long as the first part. 

It is a nice place to end the book, while also setting up a sequel. It'll also help me economically, because I can't afford to edit a 100K novel all at once. Right now I can't afford more editing on the 60K novel that has only been through a first pass. So a shorter book is the right way to go economically, and as it makes sense to cut it after the first part, that can work out. 

But (there's always a but, isn't there?) there's the issue of the cover. I found the perfect model for Thomas. So what do I do then for the next cover? And the third one, if their story ends up being that long? That's my main concern about this, because the cover I have now is so perfect! I'm not sure what to do for the next covers. Perhaps find another model to portray Leo. 

So this is what I'm pondering. What am I to do? I really am leaning towards publishing the individual parts, but the cover's holding me back.