It may have just been a shadow, but particularly in the first picture it looks as though your spine is leaning to the right. I'm sure it's just a weird camera thing because if your back was as crooked as it appeared I'm sure you'd know about it.
Complexes are awesome! You'll build testicular fortitude and add or maintain muscle while losing fat, and get stronger. I've followed the "complexes for fat loss" article, which calls for complexes first thing in a training session. Got a hell of a conditioning/work capacity boost in just four weeks of that. Body fat went from 11 to 10 and my diet was terrible. I probably should have gained fat considering how I was eating.
Mostly I've used complexes as finishers. They're a great way to end a session, especially if you feel like you still have a lot of gas in the tank. I've also used complexes on off-days (train-train-complex-train-train-complex-off), usually just working through one each day so as to not compromise recovery. I got the most out of complexes with the pre-training (naturally) so if fat loss is a goal that's definitely something to consider. At the very least, finishing a session with a complex will help get you closer to your goals.
Use the search feature and you'll find tons of great things on complexes. There's even an article called "complexes made simple" that explains the rules to build your own complex. I've followed some of the pre-existing ones and made some of my own. Seriously, complexes rock! I have yet to find a more versatile and effective tool to add to my training.