[Idea] Buff for Heal Spell

Heal is currently one of the most underused cards in the game. Here's a proposal for a buff to Heal that doesn't involve increasing the duration of the actual spell. The troops that have shields, such as Dark Prince and Guards should regenerate their shields while under heal. This would make Heal more viable in decks which include DP or Guards, and it could increase the usage of Heal(obviously) and Cannon Cart. If a person uses Cannon Cart + Heal with this new proposal, when the Cannon Cart dies and turns into a regular Cannon, this combination could allow the Cannon to turn back into a Cannon Cart depending on how much health the Cannon has.