[Brightcolours]

Tony, Arthur already has a 70D, so probably is not looking to get equivalent lenses for FF, rather looking for something that adds to what his APS-C camera already can do.

 

And yes, there is no 29-216mm f5.6-9 IS STM lens for FF. There are 28-200mm lenses and 28-300mm lenses for FF, but anyway, not a reason to get a FF camera. The equivalent for the 17-55mm f2.8 APS-C lens would be a 27-88mm f4.5 lens on FF. Lenses enough to meet those criteria: Canon EF 24-105mm f4 L IS USM, Canon 24-70mm f4 L IS USM, Tamron 24-70mm f2.8 VC USD. But again, that is beside the point (the point being that Arhur already has an APS-C camera, so can use a 17-55mm or a 18-135mm APS-C lens, if he wants to, regardless of whether he gets a FF body next to it, or not.

 

Lenses like the Canon EF 85mm f1.8 USM, Tamron 85mm f1.8 VC USD, Voigtlander 58mm f1.4 SL II, Zeiss Milvus 85mm f1.4, Canon EF 135mm f2.8 SF, Nikkor-H•C 85mm f1.8, Zeiss 135mm f2, the many 135mm f2.8 manual focus lenses from the past, even my 55mm f1.2's, Canon 200mm f2.8 L USM II, Canon 200mm f2 L IS USM, Laowa 105mm f2 STF, and so on and so on, all make FF very worthwhile for portraits. 

 

In fact, if there is any area where FF is for sure good choice, it must be portrait photography. Even with cheap or old lenses.