Heylo, my wife gets major throat irritation also, here's some suggestions I worked out for her (though she's still not on board...rawr).
1) Higher VG content. There'll be less flavour but PG can be extremely irritating to some people, even I (as a 20 year smoker) have switched to 80-100% VG. And I <3 me some thick clouds.
2) Hold in mouth before inhaling. This will cool the vape down. Don't forget that it's still being heated to become vapour.
3) Throat inhale. This is a bit harder to explain, but rather than go for a deep inhale let the vapour just past the back of throat, the moment you feel it exhale. As I said, it's hard to explain. And finally:
4) Don't inhale at all! Hold it in mouth, push out/exhale through nose or just straight out. (This is from what I've read here) The nicotine from vaping is a different beast from tobacco. It's absorbed mostly through the mucous membranes of your mouth and sinus cavity. Inhaling will help simulate the smoking experience, but it's by no means required in order to get nicotine.
Don't forget to stay hydrated, carry gum and a bottle of water everywhere you go. VG and PG are both desiccants and will dry out your mouth/throat in short time. A dry throat will get irritated/sore a lot faster than a moist one.