Thank you @Gaurav , yes I always keep it at 13 and am apprehensie to go to 10 or even 12 fearing a pop-out. For the rims, will look out if i find a good deal then will consider the 16".
Thank you @Frederic will use this in case to scout for the 16" rim and tyre
@Srikumar Thank you! for the inputs, I have not been in situations where power seemed to have been an issue in the 3.5 other than climbing the Moreeb and Faya dunes (believe have not graduated to that level yet ) and it does not bother me either, while I have been in many situations where soft sand has caused refusals and stucks and I wish I had better traction in those situations. I am willing to trade power for traction so, I would need to choose AT I suppose so that it allows me to deflate to lower pressures and since I also intend to drive in places that present surfaces other than sand - may be loose gravels and stones in Wadis the higher profile tires that 16" rims would allow may be a tad bit helpful, that's my understanding so far researching on the this forum and the web, hence this question to the experts!
Again, thank you so much all for the suggestions and insights! super helpful!