All these Australians, good job. Welcome
@Louis Lloyd - you have given yourself lots of time, the best way to walk the Camino. I do hope the path is lined with flowers, literally and figuratively.
And in answer to your question - yes, I think one pair of trousers is enough with two pairs of shorts. By leggings, do you mean waterproof over-pants? I think of leggings as tight and would go under your shorts, not over them. Good for cold days, and as nightwear.
Now onto my 12th camino (I think) I only take two sets of clothes, one off and one on. I wash each day. For me it is two hiking skirts, one pair of long leggings (the tight sort), two long sleeved silk/merino tops, one merino cardigan or sweater, a featherweight Houdini jacket, one long
Altus raincoat, two sets of underwear, a buff, a visor, one pair of crocs and one pair of walking sandals. If it is summer/autumn I add a swimsuit and maybe a very flimsy light top. In spring I add gloves and waterproof Dexshell socks. For clothing, that's it.