Floor/counter tile of what type? Vinyl, ceramic, stone. We need a few more clues and what the kitchen and adjoining rooms look like now I think. And is this kitchen space bigger or about the same size of a breadbox? Can you post some pics.
In general, for countertops, stone is the current in thing. But, I can talk my clients into glass or glass terrazo with very little convincing and they get green credits. Some really like the look of concrete countertops with molded in sinks and things.
Got any money honey? All these run in about the same range for careful measuring, fabrication and installation. Solid glass might be a tad higher since not a lot of people have caught on to the material as home countertops so there just are not so many people that can install it.
I guess the next tier down would be like quartz composite countertops, the shells companies put over those existing to look like faux granite, the solids like coian thereunder, high end formica type stuff and finally the box store looking laminate crap.
As for flooring? My clients seem tired of the smaller square kitchen tile floors and many want hardward, bamboo or cork. Stone is still popular. I don't see the interest in slate I once did though. Larger ceramic squares with earth or terra cotta tones work and especially if there needs to be a nice transition to outdoor patio areas with the same. And area rugs in kitchens seem to be back which I do not fully understand but like.
It kind of depends on what you have to work with here and how much you can spend. You will, even in this depressed market, get all the money you sink into a kitchen to improve it right back out from sale of the house.
Bathrooms can go either way. Don't try to make silk purses out of sows ears with them though. Clean all the fixtures, polish the brass, paint cabinets and update door pulls and other hardware. You will be surprised at how large you make the tiniest of of bathrooms (or kitchens) look laying the tile at an angle rather than square to the wall. And use 12x12s or something.
Or go really small with antique oyster tiles or something but with a pattern that runs at an angle and not square.