My concerns include gas mileage, insurance prices, future maintenance costs, interior room (I'm 6'2),
You could also look at a 2010 Prius, I am 6-1, there is a lot on room for the drive and the passenger that seats behind him
After 13,000km we are avg 4.9l/km
Can you get a 2010 Prius for less that the OP's stated limit of $30,000? If so, that would be a good option.
My sister has a TSX that she bought used and has had no issues with it. She got it through an Acura dealer so she felt pretty confident. She has had it 3 years or so now, so its about 5-6 years old. So if you want a used Acura, Volvo, BMW, etc I would suggest their certified pre-owned type service.
Try driving some of the cars on your list, you should be able to eliminate a few rather quickly I would think. Poor seat comfort, not enough room, etc.
There could be a lot more that could be added to the list of course, so keep an open mind.
As for lease/purchase, new or used, that is a real hot topic. I have done it all and have concluded that if I want to keep a vehicle awhile, like 5+ years, then new is the way to go. I know exactly what I am getting, it will have the options/colour I want and can live with over the long term, and I am not worried about depreciation. And a full warranty is nice too.
Used pros are that someone else has eaten the depreciation hit and the vehicle will cost less in the short term.
Cons for used are you have no true idea of how it was driven or maintained, you will have no choice in options/colour, you will get less life from it than new by the amount of kms already on it. Used is a good option if you plan on changing cars relatively soon, say less than 5 years. My sister is already looking at what to replace her Acura with and she is leaning towards a Subaru, with a turbo (funny about Albertans and their go fast mentality

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For insurance you need to talk to ICBC and see what some of your selected cars would cost. Not knowing your discount rate, etc we can not provide any idea of what it will cost and I have found that just because its a cheap car (Ford Focus for example) does not necessarily mean cheaper insurance. Our Sienna, 6 years old, costs almost as much as the Forester, 1 year old. And the Forester was more $ to buy too.
Good luck in your search and welcome to the forum!