For only smoking about 13 years and ending with ultralights it's likely you started vaping with too much nicotine to begin with.
I was a 2PAD Marlboro red smoker for 32 years and was able to quit using 18mg/ml ejuice (or 1.8% nicotine by volume), granted, I put my husband on a higher nicotine 50mg/ml (or 5%) but I bumped him down after he'd been completely smoke free for long enough but he smoked for 45 years...
You'll want something in the "mtl" category, so look for set ups that advertise that.
For a versatile pod mod the Voopoo Vinci Air is something you may like to try... I've got one and it's pretty good, you can set it for draw activation and refill with any ejuice you'd like... For coils you'll want the 1.0ohm PnP-R2 Regular Coil - rated for 10-15W...
But I would get 25mg salts to vape in it at the most... You don't need 50 or 60mg, although now that your used to higher levels it will take your body some time to adjust to cutting it down, I normally chainvape through a couple days when I cut my nicotine...
Hope this will help you some. Here's a link:
VOOPOO VINCI AIR 30W Pod System
If your not getting the throat hit you want from salts, try freebase nicotine in the 12mg - 18 mg category.. 25mg if you need, but 25 might be too harsh on your throat.