A working man earns let's say £400 in a week. The pup could potentially give him maybe 10 years work.....I know your pups are from good stuff so for me they're easily worth a weeks wages....
Could be anything Jok....when you get even a 1st cross it can throw multiple colours and types. In the making of Legbars some araucana blood was added to give a different coloured egg.....obviously the leghorn and rock to secure the autosexing ability.
The cockerel you have could be a leghorn cross - you do get lavender leghorn but without the red, also he has sizeable wattles and yellow legs.
No generally they barred all over - on some the barring is more pronounced than others. I'm not aware of any bantams as such but I guess some thing could be created with banty leghorns and barred rocks.
Brinsea are good.....till you use something like a Heka or MS. Any inc will hatch run of the mill eggs but when your hatching some sensitive breeds you'll see how good they are.
Rabid, Leghorns are what's known as a light breed - great egg layers but rarely go broody. Other light breeds are Ancona, Fresian fowl, Minorca and lots more.
If you want something to go broody you want a heavy breed - Rhodies, Sussex etc