Which starter app kit or cms / admin system to choose?

I'd note that Bonfire doesn't meet #5 on your list and *barely* meets #3. I say *barely* because most of Lonnie's attention has moved on to Sprint (https://github.com/ci-bonfire/Sprint) and, more recently, to CI4. Meanwhile, I have not had the time I would like to focus on the issues I would like to see resolved in Bonfire, and few other developers have shown a sustained interest (in terms of submitting code/fixes) in quite a while.

The pros:
- I don't think I've had to make significant changes to Bonfire itself to deal with any of the CI releases since we got it working with CI3.
- It does provide a solid set of features which are extremely useful for many types of websites.
- It gives you a lot of freedom on the public side of your website.
- Especially since getting it to work with CI3, wherever possible we override or extend rather than modify the CI core (though we do modify 3 CI files, because it was either impractical or impossible to achieve the same result in another way).

The cons:
- The admin pages are currently dependent on Bootstrap 2, and some of the HTML for the admin side is generated by a library which outputs HTML specific to Bootstrap 2. There is a branch which has updated this for Bootstrap 3 and probably works with Bootstrap 4, but I would prefer a long-term solution which removes the dependence on a specific CSS/JS framework for the admin pages.
- Some of the libraries and modules could use a lot of work (though they work well enough, the code could be improved).
- Although everything is made to be replaceable, it is not easy to extend any of the major functionality in Bonfire itself (this goes in part with the point above about improving the code).
- A lot of people group/equate Bonfire with CMS projects, but Bonfire does not include a CMS. It includes a lot of functionality which is helpful in trying to build a CMS, but you would still have a lot of work to do if you needed a CMS.

Also, since people seem to ask this about CI3 quite often, it might be worth mentioning that Bonfire does work with PHP7. It may not take full advantage of it (and, unless I'm still around to port it to CI4 some day, it probably never will take full advantage of PHP7), but I haven't found an issue running it under PHP7 in quite a while.

Bonfire

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