My experience with Hensel is limited to what I have - a Porty power pack with one head and a ringlight - so I can't tell you anything about their other heads and I know nothing about the self-contained mono lights, sorry. If the mono lights have standard 1/4" jacks for slaves (like the one Hensel head I do have) or the household plug looking connector, you can use any wireless trigger system like Wein or PW. I would assume the other mono-lights will have some kind of built-in sensor (it senses the first flash going off) in which case you shouldn't need more than one wireless receiver, but don't quote me on that since I'm not familiar with the heads you have.
One thing I can say for sure (I hope) is that once you set the output level on the heads (whether they be a pack & head system like mine, or mono-lights), those output levels will stay put when you do your flash reading with a hand-held meter. The Hensel transmitter I have (for the Porty - yours may be different) also has a feature to control the output of the power pack, up or down, but once its set, its set and the reading you get with the meter is the correct reading. (What would be the point of getting a light reading on a false setting?).
Regards,
Andy Pearlman
Andy Pearlman Studio