The moon and brighter planets sound good to me as a starting point. Baby steps and all that. I know my way reasonably well round a camera, just the astrology side I need to swot up on as some things are a bit fuzzy.
I remember as a little girl my dad taking me out on the park to look at the stars and him taking me and my sister to the Planetarium in London which used to be next to Madame Tussauds. Once that seed is planted it's with you for life.
My Canon is the EOS 300D which is a good 8 years old now and I think the equivalent now is the 600D. Think it's classed as an entry Level camera for the enthusiast but having said that it cost £735 8 years ago. My partner has the Nikon D300 and you won't get much change from 2 grand if you bought that. However as you say Canon have a fantastic range of lenses.
I still have and use a 40 year old Konica S3 SLR. Fantastic little camera with a great lens. I don't think many were sold so I think ones still in working order are fairly rare.
Anyway I'll let you know how we get on. Have you ever used Stellarium by the way?