First off get rid of the cotton candy or EM as also known. It will reduce flavor as it steeps. Second, half your strawberry and add either strawberry (FW) or strawberry sweet (cap) for the other half. This should help…
Also, if the original recipe was a 50/50 mix that makes me think that they were maybe over-proofing it a little bit so when you (and very very sensibly) wanted to go more towards a 70/30 solution all of the sudden the flavor wasn’t working. It’s my understanding that a lot of commercial flavor companies do things like add heaps of sweetener or sucralose or up the PG levels (by adding more concentrate than is necessary) in order to sort of cover for the fact that they just haven’t blended a very good juice where the different components aren’t in harmony --certain concentrates sanding off one while others are sharpening or enhancing another-- so they make up for the deficit by adding more concentrate than you normally would. I would suggest maybe searching similar recipes and see if you can find any with really positive ratings that are at a 70/30 mixture or, if you can find em, an 80/20 mixture (because that’s darn hard to do, but if you can… it demonstrates no small amount of skill on the juicer’s part).
It’s easy to make really strong flavors by adding large amounts of PG concentrates. The juices that really shine, IMO, are the ones where they’ve been able to stay within or below that 70/30 range and you STILL get hit with a wonderful, complex, subtle flavor profile.
Also, one of the best tips I ever learned for making fantastic strawberry flavors is to use a 2:1 ratio of regular strawberry (TFA) and ripe strawberry (TFA). So right now, you’ve got 7% of your mixture as ripe strawberry. Consider dropping the cotton candy as ringling so rightly suggested (props to you my friend) and do a 10% strawberry/5%r ripe strawberry mix instead. Maybe add a drop or so of sucralose as well (but no more than that or otherwise you might as well be dumping Pixie Stix and nicotine into a nebulizer).
Another option would be to still drop the cotton candy, do an 8% strawberry/4% ripe strawberry mix and then use the remaining 3% to either A) bolster the cheesecake concentrate B) add some marshmallow concentrate to the recipe or C) some combination of choices A and B. Seriously though, learning that 2:1 strawberry/ripe strawberry trick has made ALL my juices with strawberry friggin’ amazing. And if you REALLY want to go full-bore with it, get your strawberry concentrate from Capella and your ripe strawberry from TFA (I’m lazy and TFA’s regular strawberry flavor is still pretty darn good, so I just order 99% of my stuff through them, but my friend who ran a juice making company up until he and his wife out of the blue decided it was time to move and left to go teach English and Social Sciences in Alaska taught me all about the Capella/TFA straw/ripe straw 2:1 thing and it really made his mixes sing~)
I have made this juice in the past and it was great. I agree w/ @ringling the Cotton Candy or EM ( Ethyl Malto) will zap the flavor over time. I mixed this and then shake & vaped it. So I honestly can’t recall how it aged but w/ what I know now about cotton candy & flavors that contains ethy malto = EM the flavor will eventually fade.
Since you’ve already made this up I agree again w/ RIngling add an additional Strawberry a sweet one would help the ripe out more but by looking at your %s you are already up to 23%… You could always do a new batch and leave out the cotton candy altogether and add sweet strawberry then with the old batch either chuck it ( i personally vote for that as you’ll contaminate the new batch w/ EM and the new batch will fade ) or you could keep it and as you fill up your tank fill it w/ half old and half new …just a thought.