I've never used anything BUT clipless since I've been road biking. Cages scared the bejeezus out of me (to me it's like being trapped, and required too much monkeying with to get "just right") and I knew that platform pedals would keep me from being efficient (and therefore I would end up working harder).
I never had a problem. Sure, I fell a couple of times, but I never let the pedals get the best of me. I went in to it with a positive attitude. I know a lot of folks have issues with them, and I think that, in many cases, fear of the unknown overrides everything else. You are in control of the pedal, not the other way around.
It will make riding easier, for sure. I also think it's safer once you learn how to use them (which really doesn't take all that long if you give yourself time and a good/safe place to practice).
The Shimano SPD double sided mt bike pedals (many different models) are pretty easy to use. I use Speedplay as I have a bad/wacky knee and that pedal system is the only one that doesn't lead to knee pain. If you can, talk to a sports medicine doc about your knee pain and which pedal system might work for you (a good sports medicine doc will know this info...either that or I got spoiled by having one of the finest in the nation) There are lots of systems out there, and different people like different things, so the choice may not be all that easy to make!