Theres a lot to think about before you buy anything.
Do you want any internal fittings, shelves or pull out drawers/baskets, if so you need to think about the door width especially with pull out stuff,, will you need/want a central divider in which case it would be good for the doors to meet/overlap at that point.
Generally: fewer doors = heavier doors - might not be an issue depending on what they are made of; more doors = a bit more lost to overlaps when they are closed and more general faff to align when you are fitting them.
Generally, not calculating for overlaps: 2 doors on double track, 50% can be open at any one time, 4 doors on double track also 50%. 3 doors on double track, 33% open at any one time, 3 doors on triple track 66% but the extra overlap takes away some depth, either inside or outside depending on how they are fitted.
I suggest you look at the IKEA website for design ideas. Their PAX range is modular, choose box, add internals, choose doors so by scrolling through 100+ pictures of the variations it gives you loads of ideas which you can then adapt to your project. I have them as office storage in my study with 2 big but light sliding doors.
I'm not suggesting you buy IKEA, diy will be more satisfying although you might be surprised by the price of the timber you will need, but their designs are really well worked out.