About soviet names of streets they are still present in Crimea only (which is an "independent Republic" inside Ukraine), while in Odessa (which is Russian speaking as well, but not autonomous) they have tsarist names everywhere (but all signs are in Ukrainian only).
For prepaid sim-cards you don't need any registration, you can buy them everywhere, just pay!
About the fine+corruption I think I payed "a lot" and the cop knew that since I was a foreigner and used to very high fines (if I were in Italy I would have payed at least more than 300 euros plus suspension of the license for some months...), that's why he wanted me to decide how much to pay. Anyway 15 euros for me were more than fine and for him too!

About the flashing I perfectly knew that, it's the same in Italy, but in that street there was no traffic at all, that's why I was driving faster and no one could flash me about the cops!
About the Urakianian/Russian names I know, L'viv and L'vov, Kyiv and Kiev, Odessa and Odesa (really big difference!

) and so on... it's the easiest way to understand if you are speaking with an Ukrainian or a Russian!

Anyway there are quite big differences betweene the 2 languages, Ukrainian seems to be more similar to Czech and Polish, after 1 week I could "hear" the difference between the 2 quite easily.
Train tickets were sold out in any direction, not only Crimea. Also going to Lviv was impossible. We only found a ticket to Kiev with 2 days in advance, but we needed it 1 day before, so at last we took a terrible night-bus.
Anyway, waiting to see Effendi with the Father of the Country, you can enjoy most of my pictures
HERE.
With a little but important preview!