Where do you struggle? This is about filling gaps, needs and what you are comfortable with.
There should be a place in your game that you go I wish I had a club for that. I built my set as follows.
Putter, Driver (265). I had a 3 wood (230)
Found a good set or Irons 4(195)-P(125)
I don't like to hit more than a 56 wedge (85).
I had 3 spots left. I got a Hybrid (215) and then 2 wedges to fill the gap between SW and PW. I could have done another wood or 2 hybrids but I wasn't comfortable filling the bottom gap with partial wedges and didn't have much of a need for 2 clubs in the 35 yrd gap at the tops of the set.
If I went to an area with Higher raised greens maybe I'd get a 60 and trade the3 wood and hybrid for a 2 hybrid.
I play faster than most players. I don't take any practice swings and that baffles some of my buddies. I am always ready when it is my turn to hit. I walk faster than your typical players as I like to walk briskly in general. I always like to play early in the morning so that I can get done (as a foursome) in 4 hours or less. If we are the first few group, we generally finish in about 3-3/4 hours (one guy in my group is a bit of a slow player, relatively speaking). It's not rushed just a good pace.
Having said that, I don't mind playing with people as long as they can finish 18 holes within 4 to 4-1/2 hours. However, when it starts to creep into 5 hour + territory, it is too slow for me.
5 hrs is fine for me if I am out practicing. If I am practicing ( hitting multiple tee shots, trying different approaches, chipping from different spots and checking the green slopes) I am letting anyone I see play through. If I am out playing on my own in regular medal play, I'd be shocked if I took longer than 3:30.
I pick up the clubs I find and if the owner has not come looking for them by the time I'm done with my round I leave them at the clubhouse or pro shop. To me, keeping the club would be theft and I would never be able to play a found club without feeling guilty.