Hi

Simple answers:

Get the 1.75 mm filament version. The 3mm stuff does not feed as well. There is no compelling reason to go with 3 mm unless you are doing 1 mm nozzle stuff (very much *not* high resolution). I have a pile of 3mm filament and don't quite know what I'll do with it.

Go for the standard direct drive extruder. Of the bunch MakerFarm offers at 1.75 mm, it will drive the filament the fastest without jamming. It will print anything the other extruders will print.

Go for the full blown E3D, not the lite. It's not much more money and you *will* need the higher temps, even for ABS.

The three main filaments you *probably* will user are PLA, ABS, and PETG. What you use past that depends a lot on what you are trying to do. You seem to be interested in Nylon. If so, you want to look at the cost of a filament drying setup (vacuum dryer). The stuff is *very* hygroscopic. The printer has zero impact on this, it's just the nature of the filament. The same issue applies to a couple of other exotic materials.

If you want to look at something else, the Prusa I3 Mk2 kit is a bit more money, but not a lot. It has a much smaller print volume. It also has some interesting custom firmware and software. That can be a plus or a minus depending on how handy you are.

Bob