"If it ain't broke, don't fix it!" We had a very good and easy to use format before. This change is a big step backwards. Please return to the previous format ASAP.
I suspect that a site as big as Pprune was fairly close to being broke under the old Vbulletin and MySQL standards. I don't think the changes are anything to do with the look of the thing, but are more to do with the ability to search and handle a very large database. It's no surprise that it is taking a while to get the search running again and Ridley has already explained on this thread why that is so.
I think you underestimate the amount of work that it would take to change back to the old standard - it isn't just about tweaking a few colours and such.
I've just spent a couple of days updating a much smaller online system and this was for work. Danny and Co have spent a far longer time doing this for Pprune during their free time and deserve a very big thank you.