I do not predict that, but you are introducing risk. Yes you can undo some of the damage, but default trust level 1 is very hard to undo, cause you will have a bunch of dormant accounts at TL1 that really should be 0
The biggest risks here is:
- Skipping TL0 means that a bunch of accounts go through no trivial vetting process. (we are talking 30 minutes here)
- Skipping TL2/3/4 means that a bunch of hard work is left only to moderators. TL3/4 allows some super duper active and liked users to pitch in on moderation like activity.