[BigHanksCustoms]

My suggestion is to hit one of the secondary discount retailers like Marshalls, Ross, Big Lots, DDs Discounts, Tuesday Morning.

Buy an assortment of figures, commonly at those stores are:

IronMan 2 (3 3/4 inch figures)
Captain America (3 3/4 inch figures)
Spiderman series (6 inch figures)
Transformers Generations (Classic G1 inspired figures)
GI Joe vehicles with figures (3 3/4 inch scale)
DCUC Classics (6 inch figures)
Thundercats (3 3/4 and 6 inch figures, newer style)
Star Wars Vintage collection (3 3/4 inch figures)

This will give you a good feel for what the new figures have to offer, and you can figure out what would fit your collection best.

Those discount stores often sell the various figures for less than half retail price, though selection and quantities are limited. It would be great for getting your feet wet.