Ok, I still have the treadmill, Bowflex 552's and I've added in some Powerblocks (goes up to 90#) that were on sale. I like the Powerblocks better because they are more compact. When it warms up I have the battle rope and some jump ropes. I was just thinking to mix things up a little.
If you want to mix things up a little
May I suggest getting speed bag platform and of course a good bag to go with it. Every set is different depending on where you take. Never gets old and it's fun as hell, not to mention that it's excellent for hand eye coordination - "Spidy Senses" Would cost less than the above video contraption.
Added bonus is that as you progress your friends will be scared of you.
All in all it sounds like you have enough to really get yourself going. And there's always pushups with a grandkid on your back. I think you mentioned you had some.