Would you be interested in a service where you buy your own server (metal/VPS/whatever) and through an API/web interface select which profile to run? E.g. webserver (apache, nginx, ...), mail server (postfix, exim, ...), load balancer, database (mysql, pgsql, ...), or "app" (ownCloud (has CalDAV support), Wordpress, etc.)?
The idea is that the server is yours, and yours only. We manage the setup, monitoring, alarms and all the boring stuff. If you need any assistance, we have sysadmins that can help for a fee, and depending on how critical it is for you, we'd offer multiple levels of subscription with different service levels and response times.
You mention response times and priority support, and are talking about choosing nginx vs Apache. That's far more detail than I care about. I want to click a button, give you my card details, have an inbox and calendar that I can easily access on my phone, work machine and home machine, and with some level of guarantee about the security and privacy of my data. I'm not bothered about support response times - 99.9% of the time I'm not going to need it.
I want google mail + Google calendar, without the Google.
The listed roles were just to show the idea of the service; an role providing mail and calendar (e.g. Kolab) would only have a few required options (if any). Any additional detail would be optional and have our default recommended values.
I would say there are plenty of people who _would_ be interested in that sort of a service. I've been thinking about this since I wrote the above responses, and I'm fairly certain that what I want is gmail + google calendar + google drive, without the google. The more friction or configuration steps I have to go through, the less likely I am to use it.
Case in point: I'm not particularly happy with providing LastPass with my password info. I currently pay for their service. In order to transition to KeePass, I have to give up the automatic sync functionality between my devices, I have to manually back up my key database myself, and I lose the browser extensions that lastpass provides. I'm finding it hard to justify switching for the above reasons.
The idea is that the server is yours, and yours only. We manage the setup, monitoring, alarms and all the boring stuff. If you need any assistance, we have sysadmins that can help for a fee, and depending on how critical it is for you, we'd offer multiple levels of subscription with different service levels and response times.