Another vote for quartz: easy to maintain, easy to clean and easier on your dishes. With granite, you have to be careful with any good china or pottery dishes; it will chip them very easily.
I did a quick update to my kitchen before putting it on the market and used solid surface (essentially a cheaper version of quartz). However, the big thing I don't like about solid surface is the built in sink. It shows marks from any metal object like pots and pans (so no setting a pot in the sink to soak). So while it seemed like a good idea at the time to get the sink without additional cost, I would go with quartz and an undermount stainless steal sink.
The other issue is how high your countertops are. My 1979 kitchen counters are too low for me and the next house is getting a decent kitchen with countertops that don't give me a back ache from bending over the sink. I'm at a timeshare now with higher ones (I think 36") and they are great. When they put in the solid surface ones, I asked about raising the height up and they said you can add an inch or so between the counters and the cabinets for a little extra height.
In a previous house, I put in new countertops put in and didn't do anything with the cabinets. After, the cabinets looked really old and I wished I had done something. You might think about at least painting the cabinets, though make sure it's done right with lots of sanding, priming and good quality paint. I did this with the house getting ready to sell and it looks brand new.
Sue