First of all, the walking and extra 3 days a week exercise is a great start!
I think exercise can become very boring if you don't vary it. Some ideas are swimming, bike riding, fitness circuit (my fave!) for cardio, then for toning and extra exercise how about some weights either at the gym or at home? Even doing 10 mins of a mix of ladies push ups, star jumps, sit ups etc infront of the telly would be great. That is something that you can do while you're watching something and time goes fast.
You could also take a class such as yoga, pilates, boxing etc. I used to do kickboxing ages ago (I must do that again) and not only was it SO much fun, but I learnt self defense and it got me so fit and got me working, I would be absolutely knackerd after a class!
So think of things that you wouldn't normally do and that sound appealing and just go for it! If your really enjoy it, it doesn't seem so much like boring exercise.
Saying goodbye to calorie counting AND scales for a while.
Just enjoying the new and improved healthy me and embracing my new lifestyle!