Sounds fine although a clear line is defo best.
An adjustable has to be set up running but it will have a degree of self hooking properties as you say mate.
One thing I would add is that when it gets REALLY warm zigs are not always the magic answer. You still need to feed, and feed, and feed, to get their confidence up (same as you would on the surface).
Zigs are at their best when it's warm with a real decent wind imo. When it's hot with no wind the carp just want to sunbathe unless you can get them going with prolonged feeding of mixers (and sometimes even that doesn't work).