Hi Tim, you aren't asking too much... almost all of us here managed to kick smoking using vaping.
Personally speaking it was with far worse kit than you have now, so that's the tricky part. Is that last push you need really about the kit or something else?
The Adept/zlide should do everything you need it too, filled with the right amount of nicotine and a flavour you like. I'm not entirely sure buying more kit if the answer. In fact it's something I would have recommended if you didn't have it.
You can try one of the other coils, the 0.5 plexus maybe or nicotine salt based liquids (I don't like them but you might) .. but I think you need to make the decision to stop smoking those 4-6 a day first.
You need to get rid of the habit of smoking, vaping will replace the nicotine so you aren't climbing the walls but you still have to want to stop smoking. I think the problem is at the moment you are just using vaping to get you by until you have one of your rollies. ... then you are like "Ah, that's better, that hit the spot"
Forgive me if I'm way off the mark, but there is no 'best MTL kit' really. Are you using enough nicotine in it?
.. anyway we are all here to help, we've all been though it.