Ninja and Viper play very differently, Ninja has a much busier burst while Viper is just about constant attacking. Only melees that really feels super different in the same gear sub role.

Monk and Samurai are similar, Mesui and Perfect balance both allow you to press any GCD in your combo while Iaijutsu and blitz are both burst attacks tied to GCDs though MNK has a fail state while SAM doesn't. SAM has more oGCDs and no utility while MNK does, MNK also has a raidbuff.

Dragoon and Reaper are both burst phase jobs though RPR is a lot more open while DRG is rigid. The main difference between the two is RPR has a weakness dot while DRG has a two path GCD combo. They're not as unique as the scouting twins but not as identical as the striking twins.

The melees are relatively similar but can be very different feeling, I think the main problem is every single one is a burst job which is a problem for every single job in the game. Like monk blitz isn't really a good system imo, monk could work as sustained damage, I also think Ninja could of work like this too. DRG, SAM and RPR are too burst designed to get rid of it.