Forgot to add the Clootie Well outside Munlochy on the Black Isle. It's a bit freaky, but worth driving to if you are out that way. Reminds me a bit of the Blair Witch Project. There is also a wild life park on the Black Isle, overpriced in my opinion, but an option. There are several forrestry walks in that area. There is the Fairy Glen just near Rosemarkie Beach that is lovely. Also, just outside of Inverness is the Clava Cairns. Again, I wouldn't drive to it, but if you are nearby, it is worth having a wander through.
I second Winn park. It's big, just been refurbished, just a bit of a scary place with a toddler (in my opinion) as the boating lake thing is open all around. Jonah is forever giving me a fright with that.
Auldern has a huge fruit farm that you can go pick your own fruit, there is a shop to buy lovely veg there too. They have some trampolines and a few play things set up there. It is closed now, but I think it opens the first part of June.
Oh, there are so many things to do, I can't wait until I don't have to work every weekend and can get back to doing fun things!