I'm not sat in front of my screen at the moment, but I have 4 bars in general and WAR occupies three of them and doesn't even take up every button. It's actually my most relaxing job by far in terms of button bloat*. I love playing it. You have something like 25 buttons iirc. To fit these on my bar I use 1-6, a combination of shift/ctrl modifiers, and then I also use R, T, Y, F, G, H, C, and V. I'm dumb and it works out for me, so I'm sure you can do it!

*EDIT: I forgot SMN exists, never mind. SMN has like my lightest tray of all jobs that I actively play. Wow that job really simplifies. OP, if you want a light button bloat job play SMN, unironically It's like 15 buttons and they basically stay the same from start to finish.