Keeping slots well into triple figures is insane, just because it takes a while to find a particular save.
However, it's not how many saves you have, but when you make them. This game is not as bad at over writing slots, as long as you do it ideally before entering a cell, or after the cell has finished loading and spawning. I still won't over write a slot more than 10 or so times out of habit before I quit using it. But you could probably overwrite more times and be fine. Just turn off most or all the Autosave Features, they will just save you into a corner at some point if not slow things down in the game as they are made.
How I save is, one save before starting a faction or main quest major stage. A series of slots as I play along the quest line, two or three that I cycle through as things happen. Then I may make a milestone save at major faction points along the way. This way, if I have to go back and repeat something, it's not too much. I tend to follow one main quest line at time, with the side quests that come along. If you go between factions, this can get unwieldy not being able to name saves.
Then, from time to time, I just cull the list of slots that I don't need anymore like when I have finished the faction. You can't have too many slots, up to a point.