A few years ago I saw a keynote at a game development conference talking about how on the app store most developers copy successful games. The presenter (David Whatley) called it mining for gold where others have already turned up every nugget possible (paraphrased because it's been a while...).
I think that's a good way to look at this as well. As a user of statuspage.io I can tell you that they leave a lot to be desired + their pricing isn't attractive. They have however a pretty robust and compelling solution.
Can you do something that will make me leave statuspage.io (after spending hours customizing my page) and _need_ to move over to your service? If so the answer is GO FOR IT and don't look back. I have a feeling the answer is no, and that's why you're unsure, at which point I'd start looking for other problems to solve.
Peter Thiel makes a good argument in his book Zero to One that every company needs to be designed to be a monopoly. While I disagree with some of that (competition is healthy), as a founder I know the importance of your differentiator being leaps ahead and not just an update away.
P.S. - The reason we pay for statuspage.io is because we don't have to build (and maintain) the whole management system and don't want to worry about it. For any legit company it's worth it.