I love thisproject however I have a problem with the witnesses choose mecanism, aka "12 catpains of industry" or well reputed equivalent.

First (and biggest one) : who is to coopte such "captains". In a supposed decentralysed network it means a central authority somewhere or at least a consensus voting system.
Second : what if no such "captain of industry" joins in? Should we bless project founders for eternity ? (we all die some day).
Three : 12 is a too limited number. This is intentionaly set so that we can humanely follow the witnesses quality. But I do not want to ask periodicaly myself whereas witnesses are good quality or not. I just want to feel confident with the network any time.

I would suggest the following :
- no more limited witnesses number
- all wallets could optionnaly run as witnesses
- if a end-user wishes to act as a witness is has to back some "good" amount of GBYTE (prevent spam and initial amount  for serial post).
- each time a witness serial post he is awarded  more than its post cost (aka end users are prone to become witnesses for profit)
- wallets choose their witnesses in a hard-coded random fashion among all witnesses pool.