Bristly Bill gives you a free, instant-speed target effect whenever a land enters, which is perfect, because Nadu will put lands onto the battlefield, so every time you hit a land, you get to go again as long as you have a creature that hasnt already been targeted twice
It has a good balance of costs with plenty of low cost characters to get you started in the early game, and a lot of really strong characters you can rely on to clear your opponents board and stop them from outpacing you
I will be basing my analysis on the reception these generals received at the time, how they created or supported an archetype, and answer if they maintained any sustained usage
If you have a host of green creatures, however, youre bound to draw a whole hands worth of cards, maybe even more
So, you are put in a position of not just weighing the two cards against each other in a power-level sense, but in a probability-of-playing-them sense as well
With it, you can start abusing some powerful infinite combos like Animation Module + Krark-Clan Ironworks to make your commander stronger and add infinite mana