speaking from someone who's been a geo main since day 1 .... don't invest in geo.
geo has so many issues that i've lost all hope till the elemental rework happens.
1. limited to 40% res shred with specifically zhongli
2. geo characters can't break elemental shields for shit (and guess what's in the abyss soon? 3 different types of shields with 36 units to break) making you forced to use 1 or even 2 of your party slots JUST to break elemental shields.
3. constructs a fucking joke and even mihoyo has acknowledged their failure in design with absolutely no characters after albedo having one.
albedo is the prime example of geo's absolute failure. he does NOTHING without his elemental skill down that's a construct, breaks on all boss hitbox and attacks, doesn't bloom on elemental shields, limited to 3 constructs (meaning if you use more than zhongli and albedo you will start despawning your own shit) and even at C2 he's still gimped because his skill needs to bloom 4 times before it does damage.
itto's C2 was changed to 3 geo units from 4 because they know "mono geo" is fucking useless against elemental shields.
the ONLY fix to geo is 4 unit resonance - additional 20% res shred, 400% elemental application so geo can do 1-2 application to shields to break them at an average speed 1 other unit that breaks shields can.
geo is meant to be a universal element and they've gone down the "apes together strong" route but geo on it's own is fucking useless..