What bike to convert? Already have parts

So I started with a donor bike and have most of the parts I need to convert but have made some mistakes (as you do when your a newb) and I'm thinking a need to get a new bike.

The biggest issue is that the bike I have has V brakes but the hub and rim kit I got only accepts discs. Instead of wasting time and money trying to adapt a disc to the frame I have I think it will be easier and better to get a new bike that compatible.

My requirements are as follows.

Mountain or hybrid (for commuting mainly)
700c wheel size (29er)
Mechanical disc brakes (easier to convert to ebrakes I already have e-leavers from the kit and cable sensors if needed)
21 speed drive (my hub motor has a 7 speed cassette)
Large size frame (I'm about 6'2)

Everything else is a minor consideration I think in terms of getting the bike going and being safe.

So far I have shortlisted the following bikes available locally to me that fit the bill.

Norco XFR 5 Hybrid 2018
SCOTT ASPECT 970 2018
Trek Marlin 4 2018
Apollo Xpert 10 2017/2018

From what I can tell there isn't much difference between these apart from aesthetics, except maybe the Norco with its more street oritnatated design. All entry entry level running gear bolted to an entry level frame.

Does one stand out as better? Am I missing anything? :?

Cheers!

You don't need to limit your selection over mech. brakes or the delraileur shift range. The ebrake kit levers are total garbage and you don't want to use them anyway. Although I don't have a problem w/ mech disc.s. It's easy to add a reed switch and magnet to any hydro lever/perch.
And the 7-speed cassette might even work fine on a 9-speed bike given that you will end up using only a couple of gears. Besides, cassettes are cheap.
Is there some reason you need a new bike w/ big wheels? You will be paying a big premium for that. Used mountain bikes w/ 26" whl.s are a "dime a dozen" on Craigslist and generaly, hub motors work better in 26" wheel anyhow.

I don't want to order any more ebike parts as they take weeks to arrive.

The motor I have is already mounted to a 700c rim and don't want to pay to get it re mounted.

I don't think a larger cassette will fit on this hub motor.

There isn't craigslist here, there is Gumtree (I'm in Perth Australia) and to be honest, cheap bikes here are not that common. Iive in a city literally in the middle of nowhere. Can save a little bit on a bike a few years old but would probably just rather a new one so I know the history of it.

The bikes above are all around 500AUD ($370USD), give or take $50.

I agree, don't even install the e brakes, run with the better brake handles that come on the bike, particularly if they are integral shifters handles. You are smart enough to let go of a throttle when you grab the brakes right?

I would though, try to avoid a 9 or 10 speed rear gear, because if you have 7 on the motor, you would then need to at least do something else for a rear shifter. Not hard to swap out for a 7 speed shifter, or even friction shifter, from e bay.

8 speed rear shifter can work fine with 7 speed, because with an 8 speed, the difference is not so big.

Mostly, I'd say get the bike with the least wear on it, price and bike itself all about equal. Or get the best front fork of the lot.

I found a new 2018 Marlin 5 for the price of the Marlin 4. (about 100AUD off) Not much stock around as next years models are due in soon.

It has a slightly better fork and steps up to hydro brakes. I'll run with no ebrakes I think for now.