Final decison
Well, I thought I'd update this thread. I have finally decided. I will stick with my iPad4 for the moment, that is to say, till the next iteration of the iPad scheduled for later this year. My reasons for the decision were:
First, while the issue of the weight remains a problem, I think I should be able to deal with it at least in the short term.
Second, while I know that the number of complaints about the screen and Safari crashing on iOS7 on this site is probably a very small sample of iPad Air owners, nevertheless, I also think that the folk who frequent this forum are more than a little knowledgeable about their devices. So, when they report that they are having issues - and knowing how finicky I am about my devices - even a small thing would bother me. And, I really don't have the time and the inclination to return stuff multiple times to either the Apple Store or online. That said, I think as with any device the first version almost always has some issues - I have seen this with the Surface (I currently own the Surface RT 2, but I have also owned the original Surface). I am very sure that Apple will work out the kinks by the time the next iteration of the Air comes out - both in terms of screen issues, and in terms of the OS. I would probably wait for that.
Third, I sat down and asked myself - do I really need the Air right now? If I am honest with myself, then answer is no. Like many here and other tech enthusiasts, I like gadgets and would like to have the latest devices (which probably explains why I bought the original RT and the Nexus 10 just after they were released). But already having a relatively new (around 6 months old) device (which is currently under the OEM's warranty) and which is rock solid in terms of its performance etc., goes some ways in making me reconsider the need to upgrade immediately. But this also raised another question. It is probably that the value that I would get if I sold the iPad 4 today will be higher than what I would get if I sold it approximately a year from now, which is when I intend to upgrade/ buy a new iPad. Can I live with that? I really gave this some thought. I concluded that instead of selling my iPad, I could give it away to a relative would could also benefit from it. It would be a better deal, I think (obviously, this is from my p.o.v only).
So, thanks again to all who have shared your comments/ observations and suggestions.