The reality is that it is not a real framework until a group of people consider it
their framework. Everyone has a codebase...
1. Forms are tedious, but worst is upgrading your old sites to your new code base. You see all your old 'bad' ideas and it makes you wonder about all of your new 'good' ideas.
2. Best practices top to bottom
3. Fast to code complex features; easy to maintain.
4. Slow to code complex features; hard to maintain.
5. If you do the same thing on two projects, that could go in the framework.
6. The source.
7. N/A
8. A quick look at the available implementation styles
9. Everyone changes their 'style' as they learn new things. The real question is how to decide between two 'styles' that are equal just different.
10. 'Transparent' is not very interesting to me ... well designed is ...
Everyone has their own framework. Almost all of these are really the same. The biggest difference is probably naming and how people combine things to simplify. Some people combine A and B, others B and C , but the all have A, B and C. It is those combining shortcut that make a code base fast for one programmer to do the kinds of project she/he does. But it is also those shortcuts that make it not a real general purpose framework
The best thing you can to release your code and hope you get good feedback. I have had a code base that I have maintained for a long time. I upgraded it PHP5 a while back and a few other people have gotten involved in designing and coding. The code base has improved greatly from having multiple people involved. It is still being redesigned and rethought. It is probably familiar to some here as
The Skeleton Framework. Anyone is free to download it
here. Input is welcome (negative is more helpful than positive).
The thing I have learned (besides that most of my code sucks

) is that a team can produce much better designed code than an individual. We recently have had some great design input from a familiar maniac that is really going to shake up the code for the better. The fun becomes not endlessly tweaking your own code base, but having smart people present better ways to do things.