I think you'd be better served in most instances getting your feet wet and wading out and then stepping into the canoe (stern paddler).
Holding the bow as pictured is a good idea even if the stern paddler wet foots it.

Climbing in and over your gear in any landing situation is iffy at best. I can see someone taking a header real easy with a small misstep.

I understand the slippery rock/broken leg concern, but that can me minimized if you use your paddle as a 3rd leg ( maybe not hi-end graphite ones), but most paddles with the rock guards would be fine with a little care.

With bow secured as pictured the stern paddler can use his paddle and the gunnel's to walk themselves out and in safely.

Solo you get in the best you can ;D
I wear the Brookie-Knee highs, so I just wade out and step in low and quick.

I've seen more than a few paddlers dump landing or exiting becasue they got careless for a moment and forgot that regardless of water depth, you can still roll one over pretty easy if you forget where your at. :-[