Lucy has never done well on the lower protein high carb foods. They make her gain weight really easily even if the calories are the same as the higher protein. I agree that the acana formulas are awesome and are a good compromise between the lower 20-23% proteins and the higher 45% Evo type foods. You can also just give half kibble and supplement with home cooked. If you cook, make up a big soup-pot full and freeze in small portions so it's not too much work. I actually did this for a while with Lucy at one point but with the amount of food Riley eats the cooking would be a full time job.
Boil some boneless meats (chicken, beef, turkey, etc) with a LITTLE brown rice, sweet potatoes, or other whole grains like barley, quinoa, millet, , and some assorted veggies cut into very small pieces - you can buy a bag of frozen mixed veggies for example, as long as there are no onions (at least 3/4 meat and the rest grains & veggies) and if you want to add some flavour then maybe a bit of
low-sodium chicken or beef broth. You will need some calcium so for every pound of raw meat you will need to add 1 tsp of finely ground eggshells (collect your shells, dry them well and pulverize in a coffee grinder). You can also get plenty of raw recreational bones to gnaw on if she is interested. They do amazing things for their teeth. I would also supplement with salmon oil and possibly rotate through other supplements. Mix the mush with plain yogurt, or some rinsed canned fish occasionally etc. Try to vary the ingredients a bit each batch!
You could also consider feeding some canned food
.