Wy1318 is Boddingtons right? I suggest you buy a can of their Pub Ale and see what you think of it. Maybe you can find some that is not too old/abused.
Oh yes, you will need to figure out what your evaporation rate is ad collect enough wort to compensate for the loss. It would be a shame to go to that much trouble and end up with 2 or 3 gallons or wort instead of 5 or 6.
As for the discussion on using a single base malt - my last barleywine...
Let us know how it turns out. The last (and only) wheat wine I brewed had 3 ingredients (pale malt 49%, red wheat 49%, and cara-wheat 2%), was aged for 2 months in a 5 gallon bourbon barrel, and won best in show at the state fair.
I get more of a dill flavor out of Pacific Jade. I am a fan of letting the yeast (especially Belgian yeast) do its thing and see what it can contribute on its own.
I would not put the raw whiskey directly into the beer. Use it to soak the oak chips and the vanilla beans. Then add those to the beer. You can even add the flavored whiskey too. For the vanilla amount, it just depends on how intense you want to vanilla character. I put one split vanilla bean in...
The perceived sweetness could be contributed by the Munich and Caramel malt which should not be in the grain bill IMO. Not much to do about it now except try what Martin says. Carbonation should help too.
I find he character of Northern Brewer hops change from year to year. Some years they are minty, others they are earthy (woody). A pilsner might work with the earthy but I don't think I would like it with the minty. Porter or Dunkel maybe.
I don't see any need for wheat malt, crystal malt, or black patent. Make up the difference with base malt. Perhaps add some flaked barley for mouthfeel. I find the perfect balance of roast and chocolate is to do exactly that, add equal amounts of both malts. I also find that adding some special...
Why all this racking? For lagers I rack once after 14 days or so into the secondary where I lager. From there it goes into a CO2 purged keg.
For ales I might nit rack into a secondary at all unless I want to dry hop or bulk age.
The more you rack the more you open yourself up to bad things...
I think the roast malt character would interfere with the wheat character. I would would brew it without the non-malt chocolate and see what it tastes like after fermentation. You can always add the chocola (or coca nibs) later if you want. I have found the chocolate wheat to have a lot of...
I would drop the brown malt and the crystal 40 in favor of a 1# special B addition. I find it lends a pleasant plum/raisin character without the need for extended aging to get it. You can up the base malt by 1# to make up the difference.
I have brewed a similar recipe several times and been told by a beer judge from Michigan that I am spot on. My differences:
I don't worry about mixing base grain. I use all pale malt plus the crystal 40.
For hops I do 1oz at 75 min, 1oz@ 30 min, 1oz at 15 min, 1oz at knock-out for hop stand...