Hi
@tinnietel, pleased to "meet" you. An almost-old-timer here (half a century).
The ratios I see recommended (in various places, 5-15%) never seem to cut the mustard for me. I seem to need 20-30% of concentrate in a mix before they taste similar to commercial premixed juices. Maybe 35 years of smoking golden virginia has damaged my tastebuds.
Your current nicotine level is quite low IMO. Of course, if you're happy with it, that is fantastic! But if you're feeling that you're missing a bit of throat hit, or satisfaction, it might be worth trying a bit more. I saw somebody saying that yours worked out as 1.8%, and I would say that average strengths would be 3-6mg for DTL (big clouds) vaping, and 6-12mg for MTL (cig like) vaping.
I started vaping with no nicotine at all, and stayed like that for almost a year. Then one day I tried a vape from my friends device, that had 12mg in it. Oh my god, the difference was night and day. It felt so much more like a proper smoke, and I was converted. Sadly, because it's be great to be on 0 nic.
Edit to add: I agree with the others, small batches are king when trying out new mixes. It's so much easier, cheaper, and less wasteful, I feel happier to experiment more. For totally new flavour mixes I go even further and wick up an RBA and taste the mixes as I go along.