India has the tendency to use arms purchases as tools of diplomacy. That's all good mostly but somehow somewhere they lost sight to the practical aspect of it. A nation that's the size of Singapore can afford that degree of mix-bag arsenal (so long you sorted out the integration part of the problem), but a large military arm like India? The kind of globalization they're doing will backfire when there's a major conflict that last more than a month, attrition will eat through the stocks on hand and shipments ain't necessary come on moment's notice, especially if and when powers in the background want to hold things back as leverage/bargaining chip for grander scheme of things.
If they are doing it, then they have it arse backwards in more ways than one.
Firstly, only small and militarily weak nations use weapons purchases as a tool of diplomacy by using their purchases as a token of their felty, and as such, they are paying for more than mere arms with their silver. That is why few non-American companies put in more than a token effort when US vassal states like South Korea or Japan put out major arms tenders, and those who forget and actually put in real effort and money into trying to win the deals always come away disappointed and angry.
Real powers use weapons
sales as tool for diplomacy. That is the first way that the Indian approach is arse backwards.
Secondly, the golden rule of any nation that wants to remain free and prosperous is that you don't screw around with national defence. The Chinese once forgot that and paid for that folly with a century of death, humiliation and suffering. It is a lesson most dearly learnt and one unlikely to be forgotten again in a hurry.
You use commercial contracts for diplomacy, but you should never ever compromise your own national security by picking weapons based on anything other than the merits of those weapons and how well they fit within your overall defence strategy and structure. That is why for all the closeness between China and Pakistan, Pakistan have always favoured western equipment and systems in the past, and are only switch to Chinese gear after careful evaluation and conclusion that the Chinese kit has come of age and suit their needs as well as, if not better than anything the west cares to offer.
The only exception to that rule is when, as pointed out in point 1 above, if you are paying for more than just the arms when you make a big ticket weapons purchase.
I do agree with you that logistics is the Indian military's great Achilles Heel, and has said so many times before. Any country that has fought a real war will know full well that logistics are just as important, if not more so than your soldiers and generals when it comes to winning wars. Many a great general has been humbled throughout history by poor logistics.
All I have seen thus far has only reinforced by belief that the Indians do not understand or appreciate this most basic reality of war. Their leaders care too much about the paper specs of weapons and bragging rights certain status symbol weapons grant them, and not enough about how well those weapons suit their own needs or how to keep those weapons supplied with munitions during war, never mind the issue of attrition replacements or how to boost their fighting strength in a protracted conflict.
The Indian military as it stands is built for peace and the kinds of small, short low intensity conflicts against a far weaker foe that would end before logistics becomes a real concern. While it might look impressive on paper at first glance, as soon as you take a closer look, the fundamental flaws become readily apparent, as does a near fool-proof strategy of how to defeat it - logistics.
The Indian military would fold all by itself if an opponent can sustain intensive combat operations for more than a few weeks irrespective of actual combat exchange ratios. India's own generals realise this plain enough. Which is why they came up with the ridiculous idea of knocking China out of a two-front war involving Pakistan in 72 hours.
That was driven as much by desperation as it is by hubris, and is less a case of India thinking it can actually knock China out in 72hours, but more than India has to knock China out of the war ASAP or else its game over for them.
The similarities and resemblance between India's position and those of Japan's per-Pearl Harbour are starkly similar, and I fear a grave Indian miscalculation in the event of all out war between India and Pakistan, with India deciding it needs to launch a surprise attack not unlike Pearl Harbour to try and knock China out of the war before it can get involved.