Congrats! That's a super solid team for just starting out. In my opinion, it's an easy team to score well on but is kinda difficult to master. I have had Empyria since her featured patch and I still don't understand her mechanics well.
I've been playing the game since Global launch, but only very casually. Only recently have I started ultima awakening my teams which has improved my score on score modes tremendously. It'll be a while until you get to that point. Remember to look at the recommended Memory sets on that site I linked you before (
https://grayravens.com/wiki/GRAY_RAVENS) . Mathematically there's very little wiggle room for alt sets so you're just handicapping yourself if you don't use the recommended stuff. Since Memories are free/grinded, there's no reason to not go with the best. It's also worth noting that the slots you have the memories equipped in will eventually matter, so make sure you do that as the guides suggest too. The RNG in character builds happens at the Resonance level which is where it gets kinda grindy, but that's all optional and min/max-type stuff. To get 5* weapons, you will want to start grinding the Co-Op mode. I haven't done it in months, but I think it still gives you 5* weapon shop currency for completing all the weekly challenges. It's only open during certain hours so I never bother with it, and I don't need any more 5* weapons.
I have at least one team for every element and I enjoy several of the uniframes too. Uniframes are kinda in a shit situation in that if you mix them with Omniframes, they get hit with big stat debuffs. Also some content will hit them with debuffs if you use them, but their multipliers are usually crazy high to somewhat offset that. Some people run full teams of Uniframes even though they don't reallymesh together well, or some people will run them solo for max stats. Again, not something to really invest in at this time unless you really like one of the characters. My favorite elements to play are Lightning and Dark, but I also really like Qu and Haicma (Uniframes)
Alpha is all about her core passive, which some people love and some don't. I'm with you in that I like her design but her gameplay is "meh" for me. She is getting an alt in a few months that's Lightning DPS and plays like Virgil from DMC.
Here's the old CN trailer for the new version of Alpha coming out eventually:
Here's the old CN trailer for the next character I'm really excited about, Physical version of Bianca:
Here are my teams if you're interested. Nier team I rolled for limited availability but haven't even started building them yet. I also just realized that I forgot to turn the data on when I was screenshotting so it has none of the combat power data in these screenshots. Meh, it took a while so I'm not gonna do it again. Average strength is in the 5900s with my strongest characters around 6700~
Lightning
Dark
Fire
Physical
Ice
Uniframes
Nier team