Judges are also given some direction about where they are supposed to see deficiencies in adults (such as a lack of power) that shouldn't otherwise cause a successfully completed move to "fail". Judging is still of course up to the discretion of the individual judges, but I've found that a majority are very encouraging to adult skaters and they want to see you do well. That of course varies from region to region.
The adult test track was developed to give adult skaters the opportunity to earn their USFS gold medal - in that regard it's "easier" than standard track, but only in the sense you get that final award sooner. Senior moves may not be achievable for most adults, but adult gold certainly is. Each adult test is actually more difficult than the corresponding standard track test because all of them include moves from higher levels. The focus for each move is a little different than the standard track tests, making allowances for an adults inherent lack of power compared to the kids. On the flip side of that though, the adult freeskate levels are "easier" because the requirements are a little more flexible - in pre-pre for example you have a very specific list of jumps to complete, but pre-bronze lets you choose any 3 full or half jumps you want.