Exercise is a very personal thing. Some people just don't enjoy it and others love it so want to do more. For me, the most important thing is that you enjoy what you do. If you want to do Crossfit then cool, go ahead...frankly it doesn't really appeal to me...but it's far from essential.
You don't say anything about your age, level of fitness etc. This would have a bearing too, I guess, but really exercise isn't essential. It's a contributor to good health (and to great mental health, IMO) but as they say, abs are made in the kitchen.
You enjoy your evening walk with your husband? Great. Crack on with it.
40 minutes on the exercise bike 2-3 times a week. Personally, I reckon that if you're cycling at a steady state, you're not going to be gaining a huge amount from this. In my (admittedly inexpert) opinion, I'd cut the cycling to around 10 minutes of high intensity intervals with adequate recovery periods and then spend the rest of the time lifting weights.
Yes, of course, it's fine to concentrate on bodyweight exercises, but why just pullups and pressups? What about the rest of your body? I can't do an unassisted pullup or a full (non girly) pressup....yet....but that doesn't stop me lifting some fairly decent weights and working on other areas of my body.