Along those lines, if you get into a jam you can quickly log out and log into a safe seed. You can then recover your hp and stamina and switch back. All the enemies will still be around but you might have just enough hp and stamina to survive.

In your main base, make an extra portal and label it 'new' or sonthing. In your other seed put the mats for a portal in a chest. If you wander very far and can't get back easily for whatever reason, swap seeds to get the portal mats, build a portal, then label it 'new' or whatever so you can safely come back.

Alternatively, if you get stuck and are likely to die from falling or enemies, put all your stuff in a chest in another seed, switch back and kill yourself so you can get back to your base immediately without having all your loot stuck up on Mount everest.