4 quite different whiskies!
And all with merits.
Longmorn 15 is one of my, and many here, favourite "Speyside" malts...and one you'd better not get too fond of, as it's being discontinued and won't be around long.
HP12 is a nice dram, perhaps with not as much depth as the 18, but a classic in its own way - more of an "everyday' dram ...
JW Black is one of my favourite blends - again, easy drinking. One to enjoy, rather than savour...by that I mean, in my experience, malts in general require more contemplation and time to appreciate the unfolding of their character - in the long run perhaps more rewarding, whereas blends tend to taste "nice" from first hit - that's why they are created,not so much for the "connoiseur" but to appeal to the "punter", and are maybe less rewarding/challenging.
JW Green - well, it's a nice malt - a vatting of Talisker, Caol Isla(A rather pungent Islay!) Cragganmore and Linkwood(both softer speysiders)
... but i'd rather have separate bottles of its components - for example I rarely have an unopened bottle of Talisker in the house! I suspect if you enjoy Lagavulin you'll enjoy Talisker - not a million miles apart, either flavourwise, or geographically...but different! and cheaper...
Hope this helps, and enjoy your whisk(e)y journey!