Yeah if I recall Clarisse is actually supposed to be younger than Katarina.
So, I was talking with a friend of mine about ways we'd like to improve the game, and after talking for a while these were the two things we came up with
1. Some sort of IV training mode where you could +3 one stat per character. We were thinking that it could be added to the Training Tower area and splitting the level training and stat training like Main Story and Paralogues are split. We were talking about how huge of a disappointment it is when you blow all your orbs and finally get the character you want, but it turns out they're a bad IV. This way even if you got a bad character like -Atk Rein or something you could at least improve it to a neutral IV. Plus we figured it could help out characters like the Askr Trio and Masked Lucina who suffer from only being able to be neutral. We also tossed around maybe having another set of maps that would let you decrease the stat of a character to -3 but in exchange, you'd be allowed to +3 another stat on that character. We figured that by limiting it so that a stat could only be at max +3 from it's original value, and you could only improve at most 2 stats (and in exchange for the second you'd have to reduce another stat) it would keep it from being too OP of a mode.
2. Some sort of event or shop for skill farming. In the first case, you'd have an event where the event points you earn can be exchanged for skill lines or running it the way events usually run in the game where you earn X skill line at certain score level. In the second idea there would be some sort of in game shop where you use some sort of currency like feathers and exchange them for skill lines. Once you'd earned the skill lines you'd be able to go to a menu like the Sacred Seals menu where you could give the skill line to any of your characters (provided they could use the skill normally through inheritance). Either way having to constantly try to summon more characters to use as skill fodder is a pain, and we figured this could at least help lighten the load on people.
Honestly I don't expect any of these to happen anytime soon because both cut down on the amount people spend on gacha, but it'd definitely be nice to see IS implement something like these.