I also sing a little and every part of my mouth is sensitive to heat from vaping, and I found a lot of vapes and some accessories that people swear by were just not suitable for me.
I ended up with cooling unit type portables in the Crafty and Mighty and I enjoy what they offer.
I even call other vapes scratchy now!!
The Mighty cooling unit might work better with more surface area inside, and the Crafty one may taste a little better from having a smaller cooler unit.
I can consume a capsule of 0.3 at full temp 210C in the Crafty with no coughing and I can go and do some singing, maybe I'll give a little Ahem to clear my throat!
It will be much better than smoking is for you though!
I advise you to avoid talking and singing while you hold or exhale vapor, and if you ever have to perform in a smoking area again you will probably have become quite sensitive and you'll feel it, yuk!
Water filtration can help but it's not that portable. I tend to use it for aggressive sessions/tokes with thick vapor, it's something that you'll probably end up using anyway and most vapes are adaptable for it. Although I found vapes with a high draw restriction to be less suitable as the water adds even more restriction.
The temperature control on Mighty could also help you to dial out any harshness while keeping the buzz part.
Crafty is fine tuned through an app.
Other vapes with a cooling unit built in are that new Ghost vape if you're into it, and some others are starting to have a form of it nowadays.
What I found so far is if even one person mentions a vape to be a little harsh or harsher than such a vape, I will probably not enjoy the heat somewhere in my mouth or throat.
You could try searching the individual vape threads for the word "harsh" to get an idea of how some others got on.