Both platforms are likely capable of what you want to do. Many of us have used both and moved to Hubitat for a reason--in my case (and I suspect that of most), the instability of the SmartThings cloud, upon which SmartThings is dependent for most aspects of is operation. This includes all hub and device setup and administration, all manual control of devices via the app, and most "apps" (automations) except exactly two of the built-in ones under specific circumstances (no longer as hard to meet as it once was). In Hubitat, all of this runs locally (except initial hub registration), and you only need the cloud for optional components like cloud dashboard links (and should it go down, the local dashboard will still work) or third-party services that require a cloud endpoint like Alexa. Local execution provides speed and reliability that I simply wasn't getting on SmartThings. I'm sure others have other reasons, but that is mine.
As for whether Hubitat will work with what you currently have, we'll need a bit more information. If your smart switches are Z-Wave or ZigBee, they should work on Hubitat. If they are Wi-Fi, they probably won't, at least not easily, but that's really true on both platforms (hopefully this is not what you did). I'm never sure what people want when they say "camera" integration, but you can already get motion/alarm notifications from Wyze and control the "arming" of its detection in Hubitat via IFTTT (a bit more work to set up than a native integration probably would be, but it works--cloud, of course, required).
The mobile app is coming, but there's really nothing you'll be able to do with it that you can't already. If you choose Hubitat dashboard as a manual-control solution, you can "pin" a cloud link to your phone's home screen, and it will almost be like an app. 
Presence and notifications would currently require another app/workaround, but they are still possible. (Hubitat Dashboard is also not the only solution here for manual control; SharpTools.io is natively supported, and you could also set up HousePanel, though it's likely more work that you'll want to do being new.)
I also wouldn't worry about a Hubitat hub you buy now becoming outdated. It's been public knowledge that they're working on a "v2" hub for a while now, but the biggest changes are apparently just internal radios so you don't need the USB stick and the elimination of unused ports on the outside so the hub looks a bit nicer. The remaining internal specs are likely similar or (last I officially heard but that was a while ago so may have changed) identical.
That being said, despite what I'd consider many advantages of Hubitat, ST does have a few. For new users, ST might be a bit easier to use. I think Hubitat is pretty easy, but that may have been because I came from ST and was already familiar with many of the concepts. (But I don't think ST is necessarily a winner here, either--people have long made fun of the "classic" UI, which I think has improved a bit over the years, and they are currently trying to transition existing users to--and start new users on--the "new" app/UI which doesn't yet have all the "classic" features). My only concern when switching was device compatibility, but if you're starting new, you won't really need to worry about that. Even that was a minimal concern; Hubitat was not the first system I tried to move to from ST (it wasn't released yet), but all of my devices became supported by the platform within weeks and it was already the best compared to the others on day 1.
Both systems are quite powerful--both allow you to extend the stock offerings with code for custom apps/automations, for example. Hubitat has a built-in rules engine, or you can write a custom app; SmartThings doesn't (the new app might have a rudimentary one built in, actually, but I haven't explored), leading many people to explore custom SmartApps (as they are called) or one particular custom SmartApp called webCoRE (unofficially ported to Hubitat, but it's not recommended to use due to performance issues--try Rule Machine, probably the very reason webCoRE exists, or a custom app, instead). Both also allow you to write support for custom LAN, Z-Wave, or ZigBee HA devices, though Hubitat has "generic" drivers for the most common classes of Z-Wave and ZigBee devices that should work with most as-is that aren't specifically already supported.
In any case, if you choose Hubitat and get stuck, the Community forum (this) is usually quite helpful, as is the staff (who also read these regularly). Should you choose ST, I'd say the same about their Community.--though if you ask me, I'd also say you'll probably be back when you get fed up with the same things many of us (including the creators themselves of Hubitat) did.
