About material tiers, only tier 1 (pelts, wood, junk etc.) is really and easily farmable. Second tier (pipes, electronic parts etc.) is already more rare, and we expect those components to have a decent trade value among players. Third tier is even rarer, you'll find it only in special places (for example dungeons), and in very reduced amounts. Don't expect everyone to show up using Tier 3 equipment all the time, that won't happen.
Respawn time is 1 minute, to leave some time to mates to defib you if they can. You reappear in your room, and you should be able to choose to respawn in your platoon base instead if you have one.
There are no bonus rolls on equipment when crafting, as we consider it to be annoying since you'll just keep the best ones and throw the rest to garbage.
When you die, if no friend revives you, you'll have to do the way back indeed. This is mainly there to prevent easy alting/fast relog, leaving enough time to the winners to leave/reorganize. You won't need to get back naked to your stash though, no weakness or stuff like that either, as that's just a potentially frustrating waste of time. You restart immediately in your room, and you can take some time to pick your equipment and go again.