I would go with just cents, dimes fit absolutely fine in cent sizes. At wizardcoinsupplies.com you could get a pack of a hundred for like 4 bucks.
I found my brother had all his coins in a box his silver, 1/2 dimes, modern day half's, bicentennial etc he believe they will one day be worth a fortune. I'm just going to put them all in 2 X 2 and a album and give them back to him with a description of each and relative value. Ice
I agree, why complicate matters buy having more sizes than you really need. I always like to have a small selvage of mylar around the coin, and not have the edges hit the cardboard areas anyway. How much are they there?..they are 4 bucks for 100 of them, any size here in Toronto at most places. Buy them in bulk, forget the prepackaged boxed up ones in 20.
The only thing about using correct sized 2x2's is that the coin won't slide around. I once bought three uncirculated quarters. The seller sent them in silver dollar-sized 2x2's. Those coins were moving around way, way too much for my comfort. Supply prices online are totally determined by shipping costs (unless you are REALLY ordering in bulk).
I use just three sizes. The Cent size for Half Dimes, Dimes, Three Cent Nickels, Three Cent Silvers and Cents The Quarter size for Half Cents, Two Cents, Nickels, Twenty Cents and Quarters. The Dollar size for Large Cents, Half Dollars and Dollars. Oh, and I get them fifty at a time for $1.