"cloth or plastic" is usually a matter of taste, more often than not whatever you were wearing or saw others wearing when you were little. They've got a lot of differences. "Soft and discrete" is probably going to have to be plastic. Cloth is thick all the time, not just when wet, and usually needs a plastic cover. Works well for overnight and is a lot cheaper in the long run, but that's about it.
The most discrete disposable you're going to find will be some type of clothlike pullup. They're fast and easy to put on or pull off to use the toilet in public, are all too thin to bulge, and clothlike is quiet.
I have no desire at all to try cloth. I've tried several clothlike and can't say I like any of them. I go with something like a TotalDry Plus for daytime. They're textured plasic so still pretty quiet, all their diaper qualities are good, and they're cheap. If I was willing to spend more I'd go with Snuggies Waddlers (revision 1) since they're similar in many respects, but are a LOT more comfortable, have front/back elastic, and a fair amount of SAP. (totaldry are all pulp)