Welcome to COL!
You will find lots of useful tips and advice on here, as I've done, being a relative newbie. I'm sure the experienced hands will give you the best advice.
A couple of months ago I gave my Millie chicken and rice for a while to settle her tummy after a scavenging session.
I followed that with Chappie, which has done wonders for her poos, the best since I've had her, with no squidgy bits at the end.
Sometimes even all in one place instead of a walkabout!
She too has kept a steady weight.
I know that our vet also recommends Chappie.
In the past, and still for variety she occasionally eats Fish4Dogs Kibble or Eden kibble.
You might also like to look at the website
www.allaboutdogfood.co.uk.
It's also worth doing your research as to prices - Chappie tins are 14p
each cheaper at P@H than my local shop.
Good Luck!