Is it a good idea to make a coach of this guy?
Sven Jonsson
TSI = 60 , 36 years, inadequate form
Has formidable experience and poor leadership abilities

Stamina: excellent Keeper: disastrous
Playmaking: weak Passing: poor
Winger: weak Defending: inadequate
Scoring: inadequate Set pieces: inadequate

Hmm...well, the LS is not impressive. Just compare it to a external coach, Solid coaching, Poor LS. That costs 259k (or so), so if it costs more for Sven Johnson to get to solid coaching, forget about it.

Isn't experience a big factor?

Exp does not make him a better coach. the more exp, the cheaper it will be to make him a solid coach.

If I remember correctly for a formidable experience / weak leadership player it was barely worth to make him a coach instead of buying one. But poor leadership is cheaper (as KR said) so you are better of recruiting a coach from outside.

http://www.databased.at/hattrick/x-f...?file=prices#c

Here is the link for prices to convert a player to a coach.

EDIT::
527.000-592.100 US$ to convert to solid coach from formidable experience
268.700 US$ for recruiting a poor leadership, solid-skill coach
617.100 US$ for recruiting a weak leadership, solid-skill coach

fwiw, http://www.hattricktoday.org/ has a 2D match viewer that might be worth looking into. It should be downloadable soon. It's nice because I could watch Mistfit's matches and taunt him when his attack is insufficient [lol]

do physios/doctors have a huge effect?

I have kept 2 doctors on staff for about a week or 2 now. It does help the injured heal faster. The 3rd doctor (according to the x-files) doesn't pay for itself unless the player injured is the best player on your team and you really need him sooner. From what I understand, physios on decrease the intensity of the injuries.

The higher your training intensity is, the higher the chance for injuries. Physio's negate that effect. So if you train at 100% and you have 10 physio's, the risk at injuries is the same as it is at 90% intensity.