I learned my striking skills in a striking art. If you want to develop striking skills, look elsewhere than aikido. Look to a striking art where people actually strike, not where the theoretical possibility for striking exists -- it's the only way you will practice and develop proficiency at it.
What's a striking art, anyways? Striking is basically just power exiting you and entering them, and in actuality, not just theoretically, that's everywhere in aikido. The problem is just that modern aikido seems to be teaching people how to collapse away from someone else, rather than generate power into them. In a way, that's half of what all the nonsense about internal strength is about lately, just learning to strike with any part of the body, be it your upper thigh or your hip or your fist. That's entering in a nutshell, and perhaps our art has lost the ability to teach this well at all. Maybe we are, as a community, prone to misinterpret the oft-quoted "aikido is X% atemi" in lowest-common-denominator fashion as to just mean nicking someone with your knuckles. It's just a sad state of affairs that now we must go outside of aikido to learn what was specifically there in the first place and then lost to who knows.