Throw us some more information.

What part of the world are you in and what type of spots do you have open? Sunny, dry, wet?

Far as type of tree, sounds like you have two nice maples going. Time to plant another species so when the hypothetical bronze maple borer comes by you don't lose everything.

Look up:

Nyssa sylvatica (great fall color)

Cornus controversa (decent fall color and spring flowers)

Liquidambar styraciflua (great complicated fall color like your sugar maple)

We live in Southern Illinois - not far from St. Louis! So we see heat, cold and everything in between! We have a couple of acres, and our back yard is against woods. We have shade as well as lots of open sunny space, and good drainage. Thanks for the suggestions - I'll look into them.

I like variety. For the shady spots you can add color with Japanese maples which seem to come in every shape and color. Click around, get some favorites and ask for experience with them. FWIW, I have found the "full sun" rated Japanese maples look pretty ragged even if they survive in StLouis full sun. So "full sun" must mean full sun in Seattle lol.

I agree with that last statement! We have an immature Bloodgood and a Garnet that has been in the ground a couple of years, which we love. I do want some more varieties that will do well in some fairly dense shade. I've noticed at the Shaw's Botanical Garden that they have a few small ones in very shaded areas. I'm sure they will grow slower, but they add nice color and texture.