For the HK wedding, invite your parents (pay for them), brothers and sister (pay themselves), the HK banquet will mostly be friends and relatives of your future Husband and family, this banquet you will get most of the money back from the Red Packet (Lai See) gifts the guest will give, In HK at wedding, most people give money so dont worry about the HK wedding.
Get a budget as said by everyone, find a good restaurant or if you can afford it a good hotel, find out how much they charge per table for wedding banquet.
I had two wedding parties, One in HK for my friends and Wifes family and friends, I then took her back to my country for another wedding party for my Parents, relatives and friends to join.
HK wedding Banquet I nearly broke even D
My own country wedding banquet, I paid for it all in a 5 star hotel but due to currency exchange, it worked out very cheap so I was super pleased.
I think you should foremost plan a wonderful wedding for yourselves and close family in a lovely setting. This is not forgetting everyone else its you and your partners moment.
I went to a lovely wedding on Bali. There are some magical places there for example and it needn't be expensive. As formal or casual as you want. All you have to do is make sure close family can make it.
For the rest a little knees up here and then again when ever you get to Canada when you've saved up a bit.
This way you get a memorable wedding without offending anyone.
My sister got married twice, two ceremonies once in Kenya and once in München, that's also a possibility. One was very informal/casual held in a garden under a giant tree nice lunch,cake plenty of booze and the other in a church the whole thing choir reception people she didn't even know still doesn't know but they know her ....one was Anglican the other Catholic. Yes still married.