Help with first large batch please

[Robusto]

Hi all,
So after a long hiatus, I've gotten back into brewing and mead making again. Made about half a dozen 1-3 gallon batches of mead now and all have been very good. For Xmas my wife got me a freshly dumped 15 gallon bourbon barrel- its so fresh that its not dumped yet- ha ha-
I have a 5 gallon bucket of orange blossom honey and a 30 gallon fermenter, and a pound of fermaid O.

Questions:
What size batch should I start with to end up with enough to fill the barrel and have enough to top off after loss to lees racking, etc.
I've always used ec1118 and k1v for all my meads. I planned on using ec1118 because I've had really good luck with it lately. Should I stick with it or go with a different yeast?
I have been fermenting my batches using ec1118 in the low 50's and have not gotten any fusels. Is this a good temp for large batches? Will esoteric heat from fermentation be in issue at this size or is it minimal?
Anything else I should know?

Thanks all!

 

[videojunkie1208]

I would expect to lose about 2 gallons from gross lees, if you have a corny keg, you could make a 20 gallon batch, ferment it out, let it sit in your conical for a couple of months to clarify. Then transfer to your barrel, use the remaining mead to fill the keg until you get to the lees, keep it under a few lbs of pressure in the keg, and use the keg to top off your barrel for samples and angels share replacement.

Also gives you a great control to see the difference the barrel aging is doing.