Noble One
International Vice-Captain
I agree. Who else in the team understands better how well a bowler is performing than the keeper? Or pick up on a technical weakness in the game of a batsman? Or get a batsman's eye view of the fielding set-up.That said, i think the very best captains would often be wicket keepers. The motivational aspect, having the best view of the action in the house and allowing every batsman and every bowler to concentrate completely on their job makes that position perfect IMO- if it's someone well-respected, good and mentally strong enough to overcome what you mentioned in 4.
Problem is each team only contains 1 wicket keeper. Big ask for that 1 player to also be motivational, tactical, respected and have the nous to be a captain. Many keepers are quite happy to focus on their own game, remaining in their own private zone for each and every ball.
Little suprise batsman end up as captains. They have so little to do whilst out in the field.