The assumption is reasonable up to a certain point where you start to have significantly diminishing returns. The money available is finite.
Second point I agree with. The first point is more complicated. It's easy to just take the revenue figure and say that it's a lot of money. 25m or whatever the profit figure is looks big at first glance. But if that's what they have to work with the following year, when you spread it across facility upgrades and maintenance, marketing/advertisements, support staff (volunteers can't do everything), grassroots donations, taxes etc the profit figure starts to look a lot smaller.
generous wages these guys pay themselves are a big problem too.
Patrick McEnroe takes home over $1m a year from the USTA and is still allowed to do his media work on the side.
USTA Chief Exec Arlen Kantarian earned $9m in 2008.
The top suit at the dysfunctional LTA earns upwards of £600,000 per year.
At least with the players going after a bigger piece of the pie these organisations will be forced to run a tighter ship.