Bathrooms tend to be cookie-cutter layouts during an era; efficient, but boring utilitarian rooms. When fixtures start to wear out, and perhaps there is concern of some leakage, due to the age of fixtures, it provides you with an excellent excuse to remodel.
You don’t have to replace everything in the same materials and color schemes. While it saves you money to keep the plumbing fixtures in the same locations, many prefer to get rid of a tub and have a nice tiled shower installed. Cabinets and countertops can be upgraded to anything from a modern vinyl pattern to engineered stone, and medicine cabinets are definitely up for change. Some completely get rid of them, and some go from a surface mount to a inset style; it’s amazing how much larger a small bath can seem with just this little change.
Much can be done; if you want to change your old bath but aren’t sure what you would be happy with over a period of time, have a talk with your favorite contractor and find out what will work for you.