I mean the issue there is it's still a 5 year old car firstly.
Secondly yes it really is too small. I had a bike rack on a car many years ago, it's an absolute faff. One big tent, BBQ, bag of food, clothes bags, dog in the back seat. Won't fit in that boot. Scuba gear X 2 people (all the kit, 4x air cylinders, drysuits) won't fit in that boot. A trip to Wickes to pick up 6 2x4s won't fit in that car.
Agreed that a Kona will be too small.
An eNiro with roof bars and a box will do all of the above except for the bikes - how many do you need to fit in? I've not tried in mine, but I reckon you could probably just about manage 2 adult bikes with the front wheels off, and other stuff tucked in around them, but not much else.
However, that's going to be the same with most cars - even a big estate is going to struggle to fit much else in when you've got a couple of bikes in the boot.
A towbar mounted rack is going to be significantly easier for that use (hatch mounted is out as the tailgate is made of aluminium and will probably crumple like a tin can
)
Unfortunately you're running into exactly the same issue I found - a lack of affordable decent sized EVs, the MG5 is a good start, but it's not massive - my previous car was an Octavia estate, so it was quite a change downsizing from that
If it's size you want, how about something like this:
Find your next car with Auto Trader UK, the official #1 site to buy and sell new and used cars. Over 400,000 cars online. Simple, easy, quick!
www.autotrader.co.uk
Considering something similar for our next car, although unfortunately the range on them is a bit pants
BTW, have you checked your sal sac T&Cs to confirm you definitely wouldn't be liable for any repairs? You'd hope most things are covered under warranty, but you know how they like to try and weasel out of it...