It seems to me you have a couple of issues, or more, to address. Your daughter is going to be making a lot of calls in the Hamilton area. That's where she will be living and where her day to day contacts are. And you want to stay in touch with her which is LD.
The obvious option that leaps to mind is a "national favourites" option. It would allow unlimited calls within Canada to/from five or ten favourite numbers. With your number programmed as one of the favourites, you won't have to worry about how long you talk as it won't eat into your monthly minutes and there is no LD in either direction. Cost should be about $15 for 5 favourite numbers.
I don't know if Virgin has favourite plans but would expect them to. You could pay the cost to add the option to your daughter's plan and then she remains responsible for her other calls/texts to friends. And she would still have 2 or 3 favourites left over after yours and your wife's wireless & home numbers.
If she doesn't have an unlimited text option, that is probably a necessity from what I know about student's today. I would expect her wireless use to increase significantly when she loses access to your home line; she may need more minutes. How the family divides the costs and who pays what is not for me to comment.
But don't be too hasty to sign-up for a plan before your daughter gets to Hamilton. Every wireless company will be on-campus during registration week offering student plans that aren't generally available to us old folks. Look for lots more minutes than we would get for the same price and maybe included text options.
It's a nice thing that students can now get special wireless rates and carry a number with them throughout their college years. I recall the hassle and the expense and security deposits, with additional service fees several times a year, of getting Bell to install lines in residences and student housing, not to mention the issues of sharing a line with roommates [who made these LD calls?]. Now students can manage their own telephone account and take it with them to summer jobs and roommate splits and travel and when they move back home for the holidays. Pretty nice.