Why do you hate onion? How have you cooked it? It can be lovely and sweet and caramelised if you saute it. Have you done that? If not, next time you're frying something, get some frylight in the pan, chop up the onion into smallish bits, and cook it first, until it's the colour of caramel. If you still don't like that, grate it along with everything else you don't like- the smaller the bits the more they'll be disguised. (Courgettes often take on the flavour of the dish you put them in)
Cheese can be very very high fat (I have reduced fat cheese, and it's still over 21% fat, and nearly 15% of it is saturated fat, which is the bad fat). It's not necessarily bad (it's high calorie, but that's the least of your worries- eat it), but keep that in mind.
I found this site on Quavers (you may not have the cheese one, the nutritional value won't be much different):
Look at the ingredients:
It's not an exact science, but in the absence of other knowledge, I've heard it said the more stuff in an ingredient list that you don't know what it is, you can't pronounce, or has a number attached to it, the worse the thing is for you. And the second ingredient (which means the only thing there's more of in the Quavers is potato starch) in cheese Quavers is
oil 
. Think about that compared to healthy cooking- how much oil (or frylight- a spray of frylight is 0.18g) do you use as compared to the rest of the ingredients? This looks incredibly artificial to me, made in a lab not grown in a field, which indicates to me that it's in the food group "processed crap" (that food group doesn't exist, but it's helpful to think about it that way).