Sorry, having to click the spells is an integral part of the gameplay, so I won't add shortcuts...!
I do plan on reworking he encounter rate / system a bit though, possibly by making it so fights can be skipped if you've already beaten that enemy enough times. There is currently a way to insta destroy lower lvl fights by using the ability obtained in the second town if said enemy is 10 lvl or more below your highest lvl party member (I might lower this to 5 lvl in the future). There are also consumable items with that effect ^^