Hazels second ability is entirely dependant on having tokens out, and more importantly, Squirrel tokens, but she can quickly both give you an army and as much mana as you could want
This ensures consistent draws and keeps gameplay balanced
Volrath gives you lots of options since every game is a little different depending on what you can mimic
Bouncing him back into your hand gives you one lore immediately, and you can play him again to continue earning lore in a way that your opponents can not respond to
Nicol Bolas, Planeswalker cant be your commander, nor can any other planeswalker unless it specifically states otherwise
Im more and more interested in scalable designcards that have a modest initial mana value and effect, then have an additional, more expensive ability to have a splashier outcome