Hadden, in charge between 2005 and 2009, said those in high positions did not appreciate the traditions of the Scottish game, and feels SRU policies are hampering the development of homegrown players.
Australian Scott Johnson is the current head coach and will become director of rugby when New Zealander Vern Cotter takes over in the summer.
Hadden succeeded an Australian, Matt Williams, and was replaced by Englishman Andy Robinson.
He said: "In my opinion there are far too many foreign people involved at the top end of the game in our country. There is nothing wrong, individually, with a lot of the people there. We have some very fine people involved at the upper end but perhaps not enough who fully appreciate the history and tradition of the game."
Most of Johnson's backroom staff are non-Scots while Edinburgh's South African head coach Alan Solomons has recruited several players from his homeland in recent weeks.
Hadden said: "I don't blame Alan Solomons for going back to what he knows to try and make progress with an Edinburgh side that was really struggling. And he has quite clearly made a difference. But in terms of developing international players, it's not ideal, that's for sure.
"It all stems from a lack of clarity and a strategic plan for our professional teams. Even when I was coaching at Edinburgh and Scotland I was never really all that sure what the aims were."