Pete Ingham :
Match bonus is excellent. It should apply to the team being challenged too. You should be able to spend your money how you want. Otherwise all you need is 1 player in the guild challenge with a higher rating and it would be impossible to lose.
I do feel that the guild challenge needs amending. Either increase to 15 or award points to the team that wins even if they aren't the challenger.
You're simming the wrong game; try football if you just want to buy success rather than work for it.