What the estimable torealis
said about watering your paints, for sure; yellow is notoriously hard to do anyway, so don't worry if this takes a while to nail. What base colour are you using for the yellow? Averland Sunset works very well as a foundation for all the other yellow shades.
The main thing I would say is actually that the pattern itself doesn't seem consistent; the colours and the way you have them interlocking on the upper front hull suggest a dazzle pattern camo, but the rest of it doesn't really fit with that idea. So, before anything else, I'd suggest sitting down and really thinking out what this paint scheme is intended to be - is it a pattern-disrupting 'dazzle' camouflage scheme, a blending-in-with-the-environment situational camo, or (and this might just be me misreading how you have the colours demarcated on the front hull) is it more of a 'yin-yang' balanced scheme?
In either case, take the time to work out exactly how to lay the colours out across the models (and if you're using this across a whole army, on any other vehicles and individual models' armour as well so things are consistent). If it's a dazzle pattern, for example, check out how this has historically been applied to everything from aircraft to battleships:
Remember the 3 different approaches to these schemes (blending camo = you can't see it, dazzle camo = you can see it but you have no idea what shape it is or where it's going, yin/yang = we're a bunch of tofu-munching space hippies), and do some Google image searching appropriately; it's amazing what source material you can dig up with a bit of hunnting, and it can really inspire you with ideas for things. Quite apart from the obvious inspirational sources of existing military camouflage schemes and shapes, I have a bunch of folders with colours and shapes of animals, fungi, rocks, trees, all sorts of shit...it's a goldmine.
Hope this rambling helps