It seems that not every type of website/webapplication is equally suitable for this approach.
You need to take into account the considerations described by BM here:
I think this is an area where there is a lot of confusion over encryption, authentication, and "security".
Blockchains are good for authentication, but their data is public.
Hosted Wallets are good for authentication *AND* encryption so long as server-side indexing of the data isn't required. So if I wanted something like drop-box, MEGA, or Google Docs, then I would want the file encrypted on the server and only visible in my browser.
A dating website would be problematic if you expect the server to cross-reference profiles and find matches.
Social Media would be slightly less effective without server-side indexing and matching.
Identabit will be using a "private blockchain" to protect privacy. *IF* one of those private servers were hacked then the chain data could be made public. Even though no-ones account control was compromised, their financial history would have been.
I don't think its a matter of suitability as much as it is a matter of development burn time involved. We have a toolkit/network. Some will put in more effort than others to build more advanced solutions than others. Give two different people the same set of tools and ask them to build something and the results will be different based on the level of expertise and creativity applied to their work.
I do agree not all endevours are going to be easy peasy.... but it doesn't mean they are out of the question.
Yes, that's a good clarification of what I meant.
So to answer the OP question:
"How much and what type of development work is needed to realize a brownie points style gift economy platform?"
we need to take into account what role the user data plays in such a platform and how we want to manage it.
I guess some implementations might be straight out of the box, but other might require developing additional solutions for handling and securing user data.