Football doesn't work like that, that's why point comparisons and stats are nice, but football isn't maths. And people underestimate the mental side of the thing, which is very important. That's why Chelsea is in a relegation battle and people think we couldn't get worse than 7th under Moyes? I doubt it. City spent 200 million and while their individual class is better with guys like De Bruyne, Sterling and Otamendi, they are still the same Pellegrini-team, which will do feck all in Europe and will only win the title in an underwhelming "best of a bad punch"-way.
van Gaal did things good, the overhaul was needed, we needed tough decisions, lot of signings and removal of deadwood. We also needed a change in style and of course van Gaal is not able to make us perform in a good way, but I still think he improved the technical understanding of the team. Even under Fergie we were never able to control games in his last years. Van Gaal is just not able to do something with it. He did a good job with Step 1 and is now failing to do Step 2, to settle the team, get good games out of it and develope into a promising direction. If van Gaal can't do that, we need to replace him with a manager who can do it. But Moyes was never able to do that first step anyway and money wouldn't have changed that. He had money, but he failed to do anything noteworthy with it, at the end he wasn't able to identify targets, rejected good players because he didn't know them and wasn't even able to get his Everton pair or at least only one half for much more than his release clause. He was just too weak to be in a position for such a big change and couldn't make tough decisions.
At the end we need 1,2 quality signings in attack even under our new manager and I think it could be a huge difference for us and also improve us much under van Gaal, but he still doesn't look like the guy who will get the maximum out of it with his tactics and playstyle. But I don't think comparisons with Moyes are fair or that we should just mark his time here as a complete disaster. The "What has he still to offer."-topic is probably spot on, he did his thing, but can't make the next step with us and if we are just waiting and hoping for him to still do it, things will get worse.