I'm now all grain but like most, I started on kits. The Woodford wherry was by far the best kit but does not come close to AG. The all grain mash kits from home brew company are a fantastic way to learn all grain. 2 or 3 batches and you will be brewing beer your local offy can't come close to
Re the hops, use a small piece of muslin, put your hops in that and tie it. That way all the flavour gets in the beer but the actual hops are kept neat and tidy in the bag
I would fill the keg, turn on the c02, burp the air out with 2 or 3 pulls of the valve then fill your bottle's from the tap. That way the head space is taken up with c02. Don't forget priming sugar in each bottle
Not sure about coffee in ale. Sure only one way to find out :) I believe the beers shelf life is a lot longer with cold brew coffee over normal hot coffee
I made a coffee stout. It's so simple, cold brew your coffee, so steep beans in cold water overnight and add that to the water when making the brew. It was incredible, one of the best stout I have tasted.