I used a sturdy table (going underneath) for horizontal pulls, sometimes when I exercise out-doors - I look for railings etc to do pull-ups or horizontal pulls.
One thing that I think is very important, is to stop & pause at the bottom of squats ~ to eliminate the bounce factor.
I hear what you are saying re the amount of work, which doesn't seem enough especially at the beginning.
I have a quite freaky body where I can add muscle naturally seemingly at will ~ but I don't look great when I train for muscle size (more like a prop forward in union). CC is good for me because it lets me train hard but ultimately encourages me to be lighter/better power to weight ratio.
I have found that my muscles are hard 24/7 on convict conditioning rather than getting bigger, I have slightly changed shape as-well. Feel stronger & joints have stopped aching. What I really need to do is more cardio on top.
That's something I particularly liked about CC, Paul Wade constantly talks about the importance of power as opposed to sheer bulk and size.
I only had experience with shoulderstand squats so that wasn't exactly an issue but I did hold at the 'bottom', I hold all movements like is suggested.
One thing I did get with these squats was when I first started, I had some back pain when doing them, but after 3 weeks this had gone pretty much completely. Definitely felt I'd made progress in that sense.
I haven't enough experience with organised exercise to know how easy it is for me to gain muscle but after a couple of weeks of wall pressups and such, I noticed a difference. So I may be a lucky one as well.
I have a somewhat weird body shape too, I have pretty broad shoulders but relatively wide hips as well. I've yet to decide on what would look good on me because of this.
Priority number one for me should be weightloss, so I hear what you're saying about cardio, plus I know that will be really helpful for my PE efforts
I'm too shy to just go running, too self conscious, it's something I need to work on.
All in all it'll be easier to start working on these improvements once christmas is out of the way. It's cliche but I will make next year better than this last has been.