Run and gun games are 100% the definition of cool! And I truly can't say enough how much I loved Probotector (I actually knew it as that before I knew it was called Contra Hard Corps) hehe. I agree the bosses were fantastic! It had multiple routes through the game and even bosses that only showed up if you had more than one player playing. A work of art. Alien wars was awesome too.
Great ones to be inspired by.