I can speak a little about the PA tobaccos because I use those myself. The DK is supposed to be a lot like 555, but I haven't tried 555 to say whether it is. Personally, I don't like it (I can't say why, but it reminds me of hose water...). The Tobacco (Alc) is a tobacco absolute, based in alcohol. It's the same as the Tobacco (PG), but with an alcohol base instead of PG - which means it gives a little TH. I've been using the PG versionfor a while now to mix with other flavors for a flavor I'm going for. By itself, it's not an incredibly deep flavor so you'd have to add something to it in order to bring out some richness, like a real smoke would have. I've been experimenting with the PA Bourbon (Vanilla) and it's good too, but not incredibly rich. A lot of flavors have this problem - they add flavor, but it doesn't have that good, smokey feel to it. My current favorite is the PA Double Chocolate. It's not overly sweet or creamy, like you may expect from a chocolate flavor - rather, it's more...bitter I guess, kinda like dark chocolate. I typically vape it without other flavors and it's actually probably my favorite.
What I would suggest is using something that adds bitterness, or richness, like the Double Chocolate, as well as a vanilla flavor obviously (because B&M is a vanilla tobacco). Another suggestion is something I personally haven't tried but I think would do well based on the descriptions available - F'Art Vapor Wizard or F'Art Bitter Wizard. The Vape Wizard is supposed to remove tartness from the juice, giving it a more mellow, rich flavor while the Bitter Wizard is supposed to make it more bitter, which I think would be a similar effect. I have no idea how other various vanilla flavors act in a mix, so I can't really say what type of vanilla to use if you do go that route.
I would also consider cutting it with an alcohol, which increases TH, resembling a real smoke more. The formula I use is about 50% PG 48mg nic, 25% VG no nic, 5% alcohol, 20% flavor. That gives me a 24mg juice that is something like 66/33 PG/VG and gives good TH and flavor. The first hit of the day gives a really strong TH, but it gets much easier immediately after that - to where you feel it, but it doesn't make you want to cough. As for alcohol to use, a lot of people just go with a 100 proof vodka or everclear. I just use the strongest stuff I have on hand, which happens to be rum atm.
If you want, I can send you a small sample of the Double Chocolate flavoring - maybe 3oz. so you can start your trials there. I also have some other tobacco flavors I could probably send - stuff I don't personally like so much, but someone else may.