Take a backhand lesson and try to get some help with identifying your stronger aptitude. Most of us have a better disposition to hit one type of topspin backhand or the other, but without some proper guidance, it can often get frustrating and discouraging trying to make it work.
If your slice is reliable, that's good news. Don't want to be completely helpless on that wing while sorting things out, right? Nurture that stroke so that it's at least consistent and accurate enough for your needs. A neutralizing stroke is much better than a thrash-around that only occasionally lands and seldom produces a winner. Steffi Graf fans will agree (she hit lots of slice backhands...).
Considering the trouble you're having, I'd say it's worth a try. That means investing more than a week or two, by the way. The one-hander is a different stroke that will need some time to learn and trust "under fire" when trying to play a match. Expect to need some extra time on the practice grinder to digest the new habits and build the muscle memory needed to hit that shot well.
You'll probably learn a lot about your overall game as you work on this aspect of it, too. Even if the one-hander doesn't turn out to be good for you, the process of trying it will probably be "worth it" because you'll gain a better grasp of your overall skill set.
One other thought: you just might find a place for both styles of backhands in your game. I use both and a few of our pals here do, too. When I have time to set up my one-hander, my spin, accuracy and power are just as strong as my forehand. If I'm rushed by a hot shot that gets "in" on me and I need to fight it off, the two-hander is great for that. I also love it for taking a ball on the rise and redirecting it with some authority. Aggressive returns of serve? I often prefer my two-hander for its quicker set-and-fire execution there, too.
Keep tweaking, keep learning, and enjoy the process. (Thank you Jim Flick!)
