I took a quick look at Miss Hosting and it’s difficult to see what you’ll actually get, in terms of resources, which is a common problem with this sort of hosting. It’s obviously a shared plan - and we don’t know how they allocate resources. If cPanel is familiar, that’s great and may be a good starting point to get going. It’s generally accepted that cPanel is slower to load, but recently the performance has improved significantly. The advantage with this setup is cPanel WHM where you can exercise some control over the accounts and have a management solution like WHMCS which may be of more value to you as a business operation.
We started on something similar via SiteGround but moved away after doing some tests and finding that for the same price spent on a DigitalOcean server from Cloudways we could halve the load times of some of our sites. Obviously, it’s more involved and with Cloudways you only get access to certain applications (for instance, we had to drop email support for some clients as it would be just one too many things to find a solution for) but we now have a streamlined output with rarely anything so custom that this is a problem, so it works for us as we have enough knowledge/experience to run this setup. I really like the fact that we can keep putting sites onto the same server and we can just keep vertically scaling that server.
We have a ‘standard’ plan and ‘enhanced’ plan which we run from just a handful of servers, where we have a baseline site installed on each that we performance check. We aim to keep the standard site around 1.5 seconds full load, and the enhanced site runs in about half the time. We can easily adjust our server sizes to keep this performance as our client base grows. We also have some clients on dedicated servers because their sites are quite heavy. All of this isn’t possible with a typical reseller hosting package, but it does generally consume extra time. This is the right balance for us, having certain things fully managed and being able to exercise full control over some aspects but you may find that Miss Hosting is right for you right now.
Maximise your trial with Cloudways, it doesn’t look like you can get a trial with Miss Hosting, or even a monthly plan, but do some research into whether cPanel is right for you and see if you can get some performance stats about Miss Hosting. It all might help you decide which host to go with if this is what you do.
I appreciate I’ve focused only on the hosting elements of your original post - hopefully somebody might be able to support more with the CMS thoughts and other workflows.