Is it possible to get rares from clearing lives?
Yep, they'll happen like once in every hundred or so songs you play, but they're there.
Also any obvious things I'm missing for leveling people up faster? Feeding duplicates that you no longer need cuz you already have an idol of the same type doesn't seem to work very well after level 20 or so. I tried feeding some level 1 trash some other level 1 trash then feeding it to who I wanted after hitting like level 5 and it doesn't seem to be any more effective than just feeding both level 1s (actually seemed less effective).
If you're talking about rares, no, you'll have to feed duplicates of whatever you've already evolved OR given you have enough rares and super rares, any normals you've already maxed. If you get an S combo or S score, there's a high chance you'll get a normal that starts at level 9~13. Later on in the game, you can feed spare rares for additional active skill level-ups.
Later on in the game, when you've maxed pretty much all the normals, you won't even have space to keep all your trash mobs, so a common compression technique is to feed a normal until she hits 30. Alternatively, you can sell them.
So far I'm not finding the game hard in the sense of completing anything on hard for, but I find it's very easy to break your combo when you get one of those hold notes that last a long time and you're busy with the other finger mashing like 4-5 notes when the hold note ends... I mean I have a hard time catching its end while I'm distracted with the other notes.
It comes with practice, don't sweat it (or do if you're a sperg like me)
I also get nailed by hold notes that end just as my leader's combo super power thing procs covering the screen with her portrait so I miss that tail thing and...yeah.. argh.
You can turn off cut-ins in options.
So like, How hard/competitive are these events?
I'm checking the current event for reference (I do enjoy the fact they replaced Umi with Buns. Clearly I must obtain her.), and it seems like it's a good chunk of points for the SR and a lot of ranking bullshit for an actual idolized version.
They seem to be the chunk of this, and usually these boil down to a resource game which ultimately IAP wins, so...
The first events had ridiculously high rank requirements, but then again, the population was pretty tiny back then.
As a general rule. if you don't spend loveca, you can (just barely) get one SR as a point-based reward. You likely have to spend your free loveca to get the second SR, and you'll have to drop a shitton of cash to get the third (for a free skill level up or what have you). So yes, pay2win in the end, but it's not quite so bad if you only want to evolve. (URs though, goddamn.)