Good games. Don't get discouraged, but I'd say you need to focus more on knowing when you're likely to get away with certain moves and when you should use safer ones, otherwise you'll get punished badly for them. Trying things such as back slash, shadow sneak or blazer by themselves is risky since you open yourself up for a while after the attack, so opponents can just avoid it and punish you for the unsafe move.
Basically, those moves can be good, but they won't be if you pull them off too often or in predictable ways, and some moves allow you to get away with misusing them a bit more than others. For example, Shulk's neutral aerial is great because it covers a wide area around him, deals decent damage and has low recovery if you happen hit the ground during the attack, and Greninja's water shurikens are great for harassing opponents, so you should get used to throwing them out at different charges to mix things up and keep opponents guessing.
Maybe we could play some 1v1s now? Or maybe two more people could join us for some 2v2s.