Help me decide on a new tank size

[mseepman]

Well, your question really depends on a few more things than what you've listed.

Are you getting it custom built or will it be a standard tank?
If custom, then you are better off looking at increasing the depth of the tank (for both looks and ease of work-ability) than the height as the lighting becomes a bigger problem for the fuzzy sticks when you only use T5s and go higher.

Given that you live in Calgary and are doing this on a tight budget, take a look at Bow valley or Source Aquatics and see what they may have available to you. It might give you some more ideas than what you've looked at already.