Ihmo it's the worst part. I got rid of that game because of that stupid and annoying mechanic, I you don't do any combo you only gain one or two exp. points.
Well, this is kinda thing you love or hate. All SO games have cancel combo system, but you don’t have to master it to enjoy the game and have fun in battle gaining some bonus.
There should be special skill/battle aura that allows cancel combos happen automatically until your Fury gauge will gone.
Besides that, different battle tactics could be used.
For example:
1. Develop single battle skill and rise its level as much as possible. There is an accessory or synthesis element which increases attack power or EXP gain at the cost of fury. So you basically strike a single death blow, avoiding enemy attacks while you recover. Later in the game the skills are so powerful and enemies are so bold/fast, and combos will not be necessary nor useful anymore.
2. Symbology can make a huge difference. Learn some attack symbols, use them to break enemy shield, then just do a series of fast swings/BS without any combo (which could also miss the target). Retreat, repeat.
3. Exploit enemy’s elemental weakness. Prepare variety of element based skills, symbol, weapons. Use scanning and switch to character/weapon with best match and hit, hit, hit.
These tactics will allow to build up bonus gauge, and if you manage to avoid hard hits in your direction, it will keep giving you rewards.
That’s why I like this mechanic.