The Ring abilities are all tied to whatever creature is your Ring-bearer, so if that creature is killed, bounced, or otherwise neutralized, the benefits are lost until a Ring-bearer is chosen again
I dont think Commander Anthology is going to free up that many copies of anything (whos paying that much money to bust it for singles and sell them off?) so this probably has a while to grow
Based on the latest market prices tracked on TCG Stacked, Crawdaunt is worth about $0.06 USD
Getting to dodge a turn of damage and effects and then draw an absurd number of cards for the rest of the game is a complete package that probably shouldnt have cost four generic mana
Start with what makes sense for your collection right now and adjust as it grows
Whenever a permanent an opponent controls with a bounty counter on it dies, you gain 3 life and draw a card