Yes. I agree that you will be happier with the smaller (45cm) of the two frames -- based on your inseam, I presume that your height is between 5'7" & 5'10" ...
- I'm 5'9" and I would definitely choose the 45cm which has a 57cm top tube instead of the 49cm frame which has a 58cm top tube.
BUT, what kind of cycling are you planning on doing AND where do you plan to be riding (i.e., pavement OR off road?)?!?
FWIW. If you think you will be doing more off road riding than not, then a "true" 29er like the RALEIGH XIX+G might be a better consideration. There are many other 29er options ... including full suspension 29ers & 29er Hardtails which have Rigid forks.
- a 29er can handle tires up to 700x58 ...
- of course, a 29er can handle tires as narrow as 700x19 if you were to lace a pair of 622-13 rims on appropriate hubs.
If you simply want a bike whose frame can handle FAT tires, then you may want to choose a bike from their touring line (TR 7500) or a bike from the JAMIS CODA series, or equivalent.
OR, if your tire size is going to stay below 700x38 (?) then a CX bike might be a better choice.
The last two frame types (touring & cyclocross) generally have a Rigid fork ... you will find a Rigid fork is a better option in most circumstances, and when you usually want to have a suspension fork you will want one with more than 60mm of travel ...
So, the RST Vogue fork is an odd choice, IMO, to include with relatively high-end XT components, and vice-versa.
Some older touring framesets can handle 700x53 tires when fenders are not mounted, so I presume that some current touring framesets can handle 700x53 tires, too.
BTW. If 'I' were wedded to the idea of a GHOST bike, then 'I' would probably choose either the Trekking 1300 or Trekking 7500 and remove the extraneous components (fenders/lights/rack/etc.) when they weren't wanted:
The touring frame lacks disc brakes ...
If you want a 29er front suspension fork, then it will have mounts for a disc brake caliper.
BTW. The Ghost Trekking 1300 is 650€ less than the 7500 model ... you can buy a lot of components for that amount of money!