Living where I do where it rains a lot of the time, and spending days at a time in Scotland where it sometimes seem to rain all the time ...
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... I always wear a Gortex lined 2-piece riding suit, boots and gloves. I prefer non-removable waterproof linings as the garments tend to hold less water in the outer layers, but you can't get as cool in very hot weather. The Goretex is very good at breathing, if you get damp (sweat or getting caught with your jacket off in the rain) you do dry out, even when it's raining.
Always wear your gloves inside your jacket sleeves or the water will run down into your gloves.
My current kit: Alpenstars two piece suit, Daytona boots, Heine Gericke gloves.
As in all things, you usually get what you pay for, all mine was from the low end of the Gortex range, but it is waterproof (so long as you do it up correctly). But, only the inner chest pocket is guaranteed waterproof, so that's where I carry my wallet and phone (and passport if I'm going to foreign parts). To get the other jacket pockets waterproof puts the price up.
Gloves and boots, the same applies. the more expensive, the more comfortable and so on.
But, Gore guarantee the waterproofness of Gortex clothing, in the case of my boots which leaked after a little over two years, they tested them then replaced them with new, no question.
I've got water through this lot twice, once was when the boots leak as described above, and once was I got water in my crotch, I let my jacket ride up on my tank bag and the water was blown in - we get some very windy weather as well.
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Sometimes when the saddle is wet, you can feel damp where you are sitting and this can feel uncomfortable, but you are actually dry. (Never tried beads, but this could help.)
Of course, I rarely get the high temperatures some places and seasons make you endure, which does simplify my requirements.
The most difficult part of wet riding kit? Getting your gloves on when your hands are wet (which they will be from putting on your helmet). If the linings of your gloves are not attached in the fingers, when you take them off, do so pulling finger by finger to keep the lining tucked up to the tip, otherwise it's even worse getting the gloves on.
