Quick Attack>Skull Bash for recovery on Pika. QA's a pretty good (recovery) move because of the speed and the fact that you can move at all kinds of different angles, allowing you to mix-up your recovery with just QA. Skull Bash is slower, and very linear and telegraphed.
Don't use Fsmash with Ike. Like at all. The startup and endlag on that thing is horrendous. You also don't want to use Aether as an on-stage landing tool that much either. Doing that gives a lot of time to get into position to punish. Eruption's not really any better in that regard either. Quick Draw also doesn't really work as an offensive move, since Ike has to sit there while charging it and it gives time to avoid it, particularly on stages with platforms. It's fairly good for recovery though. You also need to make use of more of his moves. I know that dash attack and counter was puttin' in work for you there but Ike's jab and aerials are pretty nice too.
In general it kinda seemed like you'd just hit buttons whenever I'd get near you or look like I was gonna approach you. You also hardly ever grabbed. Gotta go for the grabs, they're hella useful in this game. Lotta characters start combos and/or get kills with it. And when you were trying to edgeguard me and cover my ledge get-up options you were way too preemptive with them and so I could just wait for you to fling out some attack and
then recover. React to how I'm trying to get back to the stage and try to read what I'll try to do, especially against characters like Robin and Space Princess&Star Cheese Baby who have few recovery/landing mixups and an upB the doesn't offer significant protection.
Besides trying to work on some of the above stuff, you'll wanna learn some of the basic combos of your characters. You were sorta lacking that too. The Pika boards and
@XenoBrawler610 would know better than I do but I think on Pika Dthrow>Utilt>Utilt>SH aerial is a thing at very low percents and there's Dthrow/Uthrow>Thunder if they don't DI away from you. I think Ike gets like Dthrow>Aether from 0%-20% and Uthrow>Fair or something too, ask the Ike boards for more.
.....hopefully that's of some use, dunno if I articulated that well at all.
I'll look and see which replays are uploadable tomorrow and post 'em here.