AnWan
Suggestion for the story, he could start looking at a second monster (maybe a monstet that can breathe underwater, so that he can fly (when he combines with ashlyn, and swim fast when he combined with his new monster). Also, maybe he could start making money as a adventurer (solo missions of course, best MC is solo MC)
Story suggestion: Seeing that the MC don’t have a golden finger or cheat. Then give him a mysterious master he runs into on a mission. The master ends up having a very large background, but not wanting to spoil his new promising student he does not reveal this fact to MC. Instead he uses this background to help the MC in the shadows. Like stopping a expert too high of a grade from attacking him so he only has to deal with at most people a few levels above him. Also finding a second partner. Maybe another weak mutated creature with a lot of potential. I like the idea of a turtle like creature. He already has attack ability with the sparrow. So the turtle will give him defense.
How about when he's trying to train his birds abilities he sees a contest for flying type monsters only where they do aerial battles and the trainer's only can direct them in hot air balloons. So he sees a poster for this contest and does one or two errands in preparation for the contest on order to gain strength. He performs well and catches the eye of some people which leads to any future opportunities
For the love of all things holy in the light novel world - please finish your thoughts! And use the proper names or words! Not everything should be word count or typed out using a phone keypad - like what I'm doing. Most of my time reading the novel is just figuring out what is happening, instead of enjoying reading the novel.