Of all the ones you mentioned, I either prefer the climbing sticks or like Deer902 mentioned, I'd invest in a climbing stand. Climbing stands are easy to pack in and out and if you get the right one, easy to assemble and use plus more comfortable than most lock ons....I use the Ol'man climbers.

The boot spikes, I'd stay away from....they will really tear up a tree and if your not used to them can be very dangerous...trust me, I climb poles for a living. The screw in steps tho practical can be a pain to install....when I used them (I now have sticks), I really worked up a sweat. The strap on steps can be very dangerous as well. If you don't get them tight, they can roll on you and you'll come down and not in a good way. ALWAYS WEAR YOUR SAFETY BELT, especially one that you can wear while climbing if your using strap on steps.

In this order is my preference:

Climbing treestand.
Loc on with climbing sticks.
Ladder stand
Screw in steps
Strap on steps.