If you like that much flavor in your juices that is ok. I have found (personally) that using less flavor gives me more flavor in my
juice. Just like Hoosier says in his blog too much can diminish flavor in your juices or make them taste off. I have read some Capella recipes that call for around 30% flavor. I personally start very low in my flavors and adjust very slowly (drops at a time) in my test batches. Needing to use more flavor in your recipes can depend on what you are using to vape. My Aga-t2 and phoenix with SS wick, I use very little flavoring in my juices while for my father I have to double the flavor that I use so he can taste it in his CE4s.
I have noticed when using Capella the longer I steep my juices the stronger the taste get. I have made a batch using 10% Capella strawberries and cream that has steeped for over a month that is bursting with flavor while a batch at 10% flavor that only steeped a week have very week flavor. I have also noticed the longer I stay away from cigs the more I can taste my juices. Taking just one puff off of a cig can make me not taste my juices well for over a week. Drinking lots of water helps with being able to taste juices as well.
If you are concerned with adding too much flavor to your juices (cost or health reasons) I would sugest buying some super concentrated flavors from Vapingzone or ECX. I just got some in from both vendors and I use around 1-2% flavor in my juices using those. For some reason I taste a slight hit of chocolate or something similar from all super concentrated flavors I have tried (~20).... but they all taste ok to great after some tinkering.