Like you, I play Magic, and like you, I hate it when I can't cast my spells. So I looked online to find resources on how many lands to play, and the best I could find was Frank Karsten's excellent analysis here. However, while his analysis is great, I still wanted a tool that would allow me to do more fine tuning. Since I couldn't find such a tool, I decided to make one.
Run 1000 simulations and reports back what percentage of those times you have enough lands to cast the spell you want to cast.
Those are not accounted for. All lands are assumed to come into play untapped.
Also not accounted for.
Good news; those are accounted for! If your hand has less than 2 lands or more than 5, then the simulation takes a mulligan. This is unless you mulliganed twiced already and only have 5 cards in your starting hand, in which case it bites the bullet and keeps.
This is the first version of this. I might add more functionality if a lot of people use it. Ideas include a mobile app and a way to import decks, so it can tell you how many turns it usually takes to play your entire hand.
My name is Mark, and you can email me at mtglandcounter@gmail.com