First of, it's all depend on what people needed.
Second of, the Plus variant are better than the base variant because they have extra stuff like mini standalone screw driver, needle and pen, so it is quite obvious.
Third of, the pliers and screw driver with bits are kind of delicate while bulky for these variant, a pliers base mt is a better option for imo, so they are a nope for me.
For the key chain size SAK, the mini champ is indisputable.
For the 75mm, the Executive, as there are not many options.
For the 85mm, the Evo array, formerly Wenger's, is basically 91mm lite. There are counterpart of most of the 91mm in the Evo series.
For 2 layers 91mm, I would say the Compact. The 2 layers is slim, yet the Compact is very packed, one of each tool, quite unique. It has plus scales benefits (there is no Compact without plus scales), 1 blade, scissors, bottle/can combo opener, corkscrew, hook/nail file combo. Other 2 layers have 2 blades, or a can opener and a bottle opener separately.
For 3 layers 91mm, the Spartan Lite. Having both corkscrew and Philips screw driver and a few other things. If you need scissors, the Climber (for corkscrew) or Super Tinker (for screw driver).
For 4 layers 91mm, this section is so packed with great variations due to the number of layers, so I have real opinion here. However, I do have an unrelated opinion. I EDC a Huntsman 2, the ugly nylon scales version, for a few years. I bought a Fieldmaster later because the screwdriver is a better option. However, I ended up never use the Fieldmaster because the smooth cellidor scales are too 'beautiful' to use. The nylon scales is just more durable and gritty, I dare say that it is better than alox scales since I still have toothpick and tweezers.
The thicker and bigger sizes are too big and wild for me.