Will infinite loops still force a draw if I have a way to end them?
You have 2 options:

(1) Propose a shortcut where you pass priority on the triggers, allowing Saprolings to be made. If your opponent agrees, you can specify the number of iterations, and then use something like naturalize to destroy one of the enchantments, ending the loop.

(2) You can let the loop proceed indefinitely, resulting in a draw. This is allowed by rule 719.5


  719.5. No player can be forced to perform an action that would end a loop other than actions called for by objects involved in the loop.




To answer your new questions:
Rule 719.4 applies in the situation where no one can interact with the loop, and all actions are mandatory (e.g., you can't set up a mandatory loop with 3x Fiend Hunter because the triggered ability is optional)

The interaction between Sanguine Bond and Exquisite Blood will cause a player to lose the game. This is because state-based actions are responsible for making a person lose when his or her life is 0 or less. State-based actions are checked before any player gets priority and before any triggered abilities are put on the stack, which means that they occur before effects like Sanguine Bond and Exquisite Blood can continue to loop.