The fact that Avacyn herself also has indestructible means your opponent better have an exile spell or exiling board wipe sitting around
As the stall player, you can capitalize on that weakness as if it were a card on the field.) Why Is This Funny
This does not match my playstyle, however
Later in the game you should be able to pay the escape cost, especially if you have any amount of self-mill (dredge, Im looking at you)

Abigale, Poet Laureate Abjure Absorb Absorb Energy Abstruse Interference Access Denied Acornelia, Fashionable Filcher Admiral's Order Adrix and Nev, Twincasters Adventurous Eater Aegis Sculptor Aether Spike Alessos and Pras, Acrobats Amazing Acrobatics Amulet of Safekeeping An Offer You Can't Refuse Angelic Cub Annul Anticognition April O'Neil, Human Element Arbalest Engineers Arcane Archery Arcane Denial Arcbound Tracker Archive Dragon Archmage's Charm Arenson's Aura Aria of Flame Armguard Familiar Armored Armadillo Artifact Blast Artistic Refusal Assert Authority Assimilate Essence Atmosphere Surgeon Autonomous Assembler Avoid Fate Axebane Ferox Bag Check Bane's Contingency Bant Charm Bar the Gate Baron Von Count Beast Mode Benevolent River Spirit Bind to Secrecy Blazing Bomb Blink Bloodcrazed Hoplite Bloomwielder Dryads Blue Elemental Blast Blue Marvel, Adam Brashear Bogslither's Embrace Bone to Ash Briarknit Kami Brine Seer Brine Shaman Bring the Ending Broken Ambitions Broken Concentration Bronze Guardian Brush Off Budoka Pupil Budoka Pupil Burly Breaker Burnout Busted

For example, if two creatures you control with lifelink deal combat damage at the same time, Aerith Gainsborough's second ability will trigger twice