[MLonlooker]

You don't seem to understand equivalence (between sensor sizes).
f32 on fullframe is equivalent to f21 on APS-C. Would you use f21 on APS-C?

Again, there is zero advantage to having more depth of field with APS-C (vs FF) as you can always match the larger depth of field with FF by stepping down more.

When considering equivalent systems, you must take in account aperture, ISO and focal length.
I remember Klaus had written an article on equivalence with examples, but it seems the article is gone :-( 
I recommend you read the DPR article on the same subject here to help you understand it better: https://www.dpreview.com/articles/2666934640/what-is-equivalence-and-why-should-i-care

Again, there is no inherent advantage to APS-C or smaller formats for macro photography.
The only reason why you might think APS-C is more interesting is because there is no equivalent lens available for FF. 
For instance a 100mm f2.8 macro lens on APS-C would be equivalent to a 153mm f4.3 on FF. So yes, there is no such lens available for FF (yet) ;-) But this has nothing to do with sensor size.
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 Technically there maybe no advantage in APSc over FF for macro, but practically, there is, subject distance is a biggy, pixel density is another .. size/weight .. I don't care..... 
 
  I don't know if you  guys have seen the work of Thomas Shahan's insect photography, it's breathtaking .......

 his was then taking images using a super basic used Pentax K200 with a reversed ringed old 50mm lens (manual focus) and a basic flash   ..... a magically calm talented man ........ enjoy!

https://www.youtube.com/watch?v=qmMcCjEU68Y 

https://www.youtube.com/watch?v=wqRn3at0H60&t=204s

 For all except portraits and the occasional landscape I'll shoot APSc .....  to keep my distance from these capricious easily spooked critters and to have a greater DOF straight off the bat with a higher pixel density ....... and when you crop noise equals out .... many prefer M4/3rds to benefit from more of the same above reasons .... 

  You could apply the same equivalent reasoning to medium format for macro, but it makes little sense ..... 

I think macro is best adapted to the APSc sensor not because the equivalency theories are flawed, they aren't, but the suitability of FF has a few drawbacks that APSc adapts to more easily.
 
               MLonlooker

[toni-a]

Toni, your example simply shows that a 85mm f1.8 fullframe lens mounted on an APS-C camera acts exactly as a 130mm f2.8 lens would on fullframe...
It's a consequence of the crop factor.

Talking about macro, if you really want to carry the lightest/smaller gear, then you should strongly consider an MFT system such as an Olympus/OM body with the 60mm f2.8 macro. This lens is super tiny.
Such a system would be equivalent to:

- 120mm f5.6 on fullframe
- 80mm f3.7 on APS-C

Even greater gains ;-) (at the cost of equivalent aperture obviously).

I was just suggesting you keep the macro lens, anyway, I use mostly full frame except beach and pool shots where I use Olympus Tg5 (because it's waterproof)
APS-C is just a backup system when I don't want to lose time  swapping  lenses and prefer using 2 camera bodies instead.
you can do whatever you like  
When it's about shallow DOF it's obviously full frame myself I use RF 85 and 35mm primes and dropped APS-C primes. For the rest both are good, I don't shoot macro but I don't like very lengthy  Minimum Focusing Distance. And that's  why I sold EF85mm and bought RF85mm, and that's why during 5D days, I used to  prefer 100 macro for portraits over 85f1.8 .
 Of course minimum focusing distance won't change between APS-C and full frame but angle of coverage will.