Yes modding can be very conservative or u can go all out.
Personally, I like up to 4 or 6 maximum small mods at the absolute outside.
If you go crazy you don't mod the game but end up totally changing the games personality. Like a woman with make up if you know what I mean. There's enhanced and there's over the top.

If it takes more than 30 seconds to talk about the machines mods, u may have done too many. Lol

There is definately money in it.
I am all behind Swinksy doing mods for all the latest pinnys cause I would like to give my $ to a Aussie pinball forum member. That latest tower mod Stern is doing for TWDead looks great. Simple but effective.

2015 will be the year of the mods.