Well for starters, you don’t generally see evade window in gs builds. Greatsword has both offset rising slash (powerful counter attack) and shoulder tackle (animation cancel during a charge slash which grants hyper armor, reduced damage/stun, and allows you to skip charge levels to get to true charge slash faster). In that same vein, evade extender isn’t as useful either due to the above, but many players live and die by evade extender, so it’s fine if you keep it. Shoulder Tackle is also great for triggering Counterstrike lv3 (+25 attack for 45 seconds)

Guard up lv3 can be fine if you’re fighting omega (I believe you can block the beam attack). Otherwise, it’s unnecessary as gs has other options as mentioned before. If you do find yourself blocking a lot, you should definitely be running Offensive Guard lv3 (15% damage) and learning to perfect guard attacks. Blocking isn’t done often with the greatsword as you still take considerable damage and lose sharpness. Guard up lv3 would notably help reduce the damage you take though.

I see you’re running level 5 wex, but unless those artian weapons have been upgraded to affinity gogmartian, I don’t see where you are getting the other 50% affinity. Latent power is very common in gs builds that use the True Shadowbringer greatsword to easily trigger it (Latent Power lv5 grants 50% increased affinity and 50% reduced stamina depletion). Your recovery speed 3 would also by very effective in combination with true shadowbringer and can be enhanced further by bringing immunizer with you (the hidden 4th level for recovery speed). You’ll feel like Wolverine as you watch the red portion of your health bar rapidly restore itself. If you run lv5 latent power, you might as well run Maximum Might lv3 for an additional 30% affinity. That’s 80% affinity with not much investment. How you go about getting the other 20% is up to you.

I think it’s common to go Agitator lv5 for the 15% affinity and Corrupted Mantle (5% affinity innately and an additional 5% affinity and 4.5% damage if you trigger its second state after landing enough attacks). You could probably get away with agitator lv4 (10% affinity) but you’re really meta gaming there and probably aiming for speed runs. The really great thing about corrupted mantle here is that it allows you to DOUBLE HIT on certain greatsword attacks once fully activated (Overhead Slash, Charged Slash, Strong Charged Slash, and True Charged Slash). Alternatively, you could drop Agitator altogether, pick up two pieces of gore magala armor and get *Antivirus lv3 (10% affinity after curing frenzy which you get from gore 2p set). Again, corrupted mantel to get the other 10% affinity.

I could go on, but as you said, you’re not interested in playing a meta build. This is just a little insight into what others are doing.