I'm glad to hear that Newt is starting to settle down somewhat. It's going to take some time and patience while working with her to sway her to your way of living. I think a lot or her habits are results of how she was living before she decided to vacate her previous home and come to live with you. In regards the meal time problems, I think I'd try to feed her before I ate and see if this would stop the problem of her begging if it does then you could use it when guests came around and maybe that would keep her away from the table where you and your guests are trying to eat. As far as the wee wild ones go (kittens) I have had no experience with them, so I can't make any suggestions.
Re the cost of canned food: I think I'd be trying to find 12.5 ounce cans of cat food rather than the 5.5 ounce cans. I was just into the Pet Value website and looked at the Wellness chicken formula cat food for an example, and buying the 12.5 ounce can over the 5.5 ounce can would save you about $ 0.12 an ounce, and if you're going through a hundred cans a month, that's 550 ounces, which would make a savings of about $66. This could help the budget a wee bit as well.
I hope these suggestions will help you.