1. As in http://www.westlord.com/wallpaper/osensei-021/
? I associate this pose with an older Ueshiba who no longer planted people into the mat at the end of iriminage/kokyunage.
2. I grew up with the Ki Soc style "ki tests" which are grouped into different types, and in our dojo looked very similar to the recordings of O-sensei (pushing with the whole body weight, shoving etc). I've seen them done in a very weak fashion as well though.
3. I'm not sure exactly what you're saying here (I thought I did, then re-read it and the link a few times). Maybe this has more to do with the development of Kendo over the last 50 years?
4. These guys had been studying their own arts for a long time. When you're used to the way of studying a martial art, and committed to learning intensively from a good teacher, you can progress very rapidly.
(Anecdote time: I was training in a dojo in London and a new guy joined who was a trained dancer. First technique, he sat and watched the sensei demonstrate it, then got up and did it. Perfectly. Sensei showed a more advanced version, he did it. Next class, and next week, he could reproduce every technique from every class he'd attended, at a level that put most of the class to shame. Of course, his ukemi was less good, and he didn't always understand what he was doing, but his training gave him a massive head start on both learning a physical movement and the feel of the aiki between uke and tori).
5. How many people here, how many aikidoists in the world, are full time teachers (and I don't mean unemployed apart from teaching twice a week at the YMCA), voraciously studying both from other aikido sensei and other martial arts teachers? I probably know less than 10 people I'd say that about, but they relish challenges (at the least, someone is going to learn something - hopefully it will be them!). That's where its gone - don't look for it in a McDojo.
As an aside, the influences on someone looking to augment their aikido are very different to those Ueshiba had - BJJ, JKD, Krav Maga... I can't help thinking that a 'modern Ueshiba' would get sniffed at by the aikido community for not doing "real" aikido(TM).