I usually like riding in the rain. I just finished a day's work in the rain. Rain doesn't really bother me that much if I am prepared for it clothing wise.

Having a good quality jacket is a must for me. I bought an MEC one in Canada several years ago, and it has served me extremely well. But the key factor is that it has pit zips. They allow me to wear the garment as a wind jacket, wet-weather jacket, cold-weather jacket... the only time I wouldn't wear it is when the weather is fine, sunny and above 15 deg C. I very rarely get saturated with sweat on the inside of it.

I've been through the mill with rainpants. Currently I have a pair purchased in France last year. The biggest problem is allowing out the sweat that builds up on the inside. THAT can become quite old very quickly around the crotch.

On several randonnees, I have ridden without waterproof leg protection, relying on leg warmers or Target tights (women's section, used to be $17 a pair, in black of dark blue). At a pinch, I have put plastic supermarket shopping bags on the front of my thighs under the tights to ward off the cold.

The most significant issue for me is keeping my shoes reasonably dry or at least comfortable. Dare I say it, but mudguards do help to an extent, but if in a downpour, nothing will save the shoes. I have had various overshoes, but the problems with cleats and overshoes is that the water seeps up from underneath (less if there is a front mudguard). Riding with wet shoes even in moderate conditions can become uncomfortable because of the heat loss through evaporation.

Layering is, for mine, an essential element, and you should start riding on a wet, cool day slight colder than you would feel comfortable.

In wet conditions, it's almost a given that you are going to feel wet or at least damp on the inside no matter how expensive or "good" the outer garments are. The essential thing is that wind protection will reduce the heat loss as water evaporates. That's where the overshoes do excel.

Others may recommend SealSkinz, and they may work for you. I may be interested in using them if I ever get around to buying cycling sandals (but since Shimano changed the design of theirs, that is unlikely for the immediate future).

In moderate temps, just a good waterproof jacket will suffice. In warm weather, you might not need to bother with anything other than what you are riding in.

Just also be aware that whatever water that is soaked up by your clothes and shoes (shoes in particular), it will weigh a fair bit.