I was lucky enough to be able to redesign my kitchen a few years ago. I won't repeat the many great suggestions others have already mentioned, but there is ONE thing I did in my kitchen that everybody who sees it thinks is just the best thing ever (and i do, too) and I have my sister to thank for it.
Like most folks, I wanted a pull out trash container. My sister, a dental assistant, happened to be visiting as i was designing it and I was showing her my plans. She suggested I have a hole cut in the granite over the trash can so I could just throw trash in and not even have to open the drawer to dispose of things...you see this in a lot of dental offices.
I talked to the granite folks and they said it would cost about another $100 to cut the extra hole. So, I had them put a rectangular (well, rounded rectangle) hole toward the back of the counter right over the trash can drawer. The hole is big enough for the average meat tray (hence the shape), but back far enough and thin enough that the counter surface is still very useable. I wouldn't have done it if the hole had to be so big I lost use of that bit of counter. FYI, I just measured the hole and it's 10 wide x 4 deep.
I can't tell you how much I love this feature of my kitchen and how many times I've thanked my sister for her great suggestion. If you do this, make sure your hole ends up being over your trash can...you'll have to work with whoever measures for your counter tops to make sure they see your trash can in place. I didn't have a problem with this, but if you didn't think about it in advance, you could end up with a hole that is only partially over the can. that would be awful.
The one and only drawback I've found is that since I put the hole at the very back of the trash can so that it wouldnt affect my ability to use the countertop, I have to throw trash pretty much straight down into the hole its not a proble for me, but most people will throw it toward the back on an angle...so if I have a lot of kids or even adult guests, the next time I change the trash I have to bend over a little extra and grab the things they threw in the hole, but at such an angle it didn't make the can. Actually, most of the stuff still goes in the can, just not everything. A small price to pay for a fantastic convenience.
When people come over, everybody loves this cool feature...the folks who have renovated their kitchens already usually smack their foreheads wishing they'd known about it before they had their new counter tops put in. Again, I'm so glad my sister was there that day!!!!!!
Have fun with your kitchen. The renovation process itself is painful, and you will ask yourself several times why you have done this to yourself (this is usually while you're doing something like washing dishes in a bathtub at midnight) and how it could possible be worth it, but it will be!