So yeah we do this. Our product runs in 3 public clouds (working on 5), single VM, etc. and our customers install it themselves. We're helm plus Replicated. AMA.
What I found is that when doing such review, you realize 99 of the template variables are not relevant for you and the one place you need to template is missing a value. Just extracting the rendered manifests and modify them by hand from there becomes more maintainable. Like you say, there is a very limited set of common denominators.
For smaller orgs, just running a single container and increasing the Node size takes you a very long way. That doesn’t need helm.
Also curious what issues you've seen replicated prevent.
Replicated saved work by handling a configuration gui for the end user, licensing/ entitlements, support bundle collection, private image proxy, things like that we didn't want to deal with.