Guidance is 1 action. Search is also an action, if you want a roll. Otherwise, it's passive perception for you, and Guidance doesn't help there.
That's okay, it's the rules. Disagree all you want.
So... you aren't casting spells subtly all the time? Need verification on this, because it opens a whole new realm of vectors -- "send an illusion, get nuked, ID sorcerer," kind of thing. Neat!
You can't, your only trick is the Retriever, which is actually arduous and time consuming (months, likely) with lots of slow travel destroying everything in your path and earning lots and lots of enemies. It's not actually useful. Plus, when the retriever falls 600+ ft after being summoned (you have to stay high because of Rangers!), it'll start off badly banged up.
And, again, the DMM is not "personally acquainted" with the targets you're trying to Retrieve.
Well, you can't Inspire Leadership from 600 feet up, so maybe the Ranger attacks during your daily, timed routine of speechifying? I mean, speeching for 10 minutes per 6 zombies is quite some time, yeah? As I said above, the zombies, even with doubled hp from temp, aren't really a threat at all. Plus, you've used your 7th level slot on a daily basis, so how are you getting the two Finger of Death zombies a day, again?