I think one point Indian friends here must understand that if Russia wants hard cash (which is True BTW), forces opposing Russia (US and Europe) would like to stop that. This can be done in number of ways. By providing better mil tech to India than the Russia (and I think it is already happening. P-8I, C-17, Apache etc.). This way they will succeed in preventing Delhi to sign any further larger defense deal with Moscow. On the other hand, if Russia sells anything to Pakistan the order will be much smaller and would give little revenue of Russia. Plus the US can even put pressure on Pakistan not to buy Russian stuff. The US may offer PAF some more F-16s to prevent any such deal.But Pakistan, on the other hand, has its own requirements in which shifting balance of maritime aviation in Arabian Sea is an emerging challenge due to inclusion of aircraft carriers in Indian Navy. So, inevitably for Pakistan it would be prudent to go for a twin engine fighter with longer range for this specific need (PAF or PN; who would use them is immaterial at this point). So impetus for both Pakistan and Russia to enhance cooperation is there. Pakistan cannot deter challenge posed by Indian carriers by inducting its own carrier so naturally second best choice is to increase the number of options to neutralize this threat. Su-35 or any other navalized flanker would fit into this role. So, I would not say that SU-35 just has no chance in PAF instead to me the decision will be based on enemy's capabilities and challenge posed and by looking at the current and future challenges, SU-35 is certainly among the best choices Pakistan has at the moment along with Chinese option. Indian factor would not matter much in this regard.