Dark Elves for Dad

Okay, my dad did dark elves and wants some more for christmas,
He wants(for sure)-
Cauldron of Blood
Manticore
I would also like to get him-
Shades(how many should he get)
Witch elves command
Executioners command
Assassin
So please telll me if these would b good gifts(he wants them all)
Also how many Shades should i get for him
And should i get him more than one assassin, or should i get him Shadowblade

2 boxes of Shades would be enough (10 shades total). Assassin's aren't as useful in 8th as they were in 7th since there are huge blocks of infantry now instead of 5-10 man units that could easily be cut down by the assassin almost single handedly, so I'd say only 1 or 2 honestly. Witch Elves are good, a little too squishy for my taste, but that's elves for ya. They are especially deadly when backed by the Cauldron so they'd be a great buy in that respect.

If those are what he wants they would be good gifts.

The number of shades depends - if he's building a combat army then 10 should work. If he's building an avoidance army then he will probably need 16 or so total.

I wouldn't take a second assassin or the named character.

For the commands, 1 of each would work to start. Otherwise get him the Exec command and 1 command group for each unit of witches he runs.

for the command he already has, 5 executioners, and 5 witch elves, also how can i model a dreadlord on the manticore