I don't have much experience with switches other than the kalih box reds that shipped with my first mechanical keyboard. They feel fine to me I suppose. I don't think I will like tactile switches, and I can't have clicky switches because of how loud they are, so I guess that narrows me down to linears only. Beyond that, I have no idea what I would go with.
Same thing with keycaps to an extent, though I think I have a better idea of what I would like: double shot pbt (for durability/no abs shine) with a spherical profile. I have tried keyboards from old computers like the Atari 800 and I remember liking the feel of their spherical keycaps. I am mostly afraid of the spherical keycaps being too tall (especially after seeing how tall SA keycaps are), which is why I was considering MT3 until I realized that nearly all their sets were abs only... I was also considering Keychron's "KSA" profile keycaps, but I don't see them get mentioned much, and they might be too tall for me as well.
I unfortunately do not have a switch tester. The problem I have with switch testers is how much they cost. That switch tester is only $30 cheaper than the entire keyboard I am buying (for the cheaper acrilic one)! The smaller cheaper ones won't be as helpful either. I wish there was a company that let you rent a giant switch tester for a week or so so that I could test a ton of switches without wasting money on the full cost of the switch tester.
I guess I could just try to return it after, but that's a lot of hassle.