OP referring to cedar trees? Although I wouldn't mind pine trees being added as well! Towering pines might add a sense of depth we haven't seen before. And even dwarf trees that stop growing once they've reached a certain stage. Similar to Japanese maples, which would definitely be a welcome addition. Along with anything else they can dream up besides wimpy bamboo. We should have the option of planting trees that grow larger as time progresses, or not. Mainly what I'd like to see is us players being given the options to create exactly the environment we want, as far as landscaping goes.
A few more ideas: bare trees in winter, new growth in spring, tree trimming, damage during storms. Wind would be cool too. Meaning more barren areas would be windier. Guess I'll stop here.