So, the best of what I have made of the comments:
1. Our spending will be less than those above. They have potential to spend bigger on better players.
I disagree on the most part, because our intent early on is to spend a lot while selling on high-value, less valued squad players. I agree, it's possible, but the argument that those spending more win more is disproved with your values. Man Utd won, despite spending less than Chelsea and City, and Arsenal finished higher than the larger spending Spurs. What I can make out, is that most of these clubs don't have depleted squad depth. All of them have 2 players in each position capable of playing, in some capacity whether regular or non-regular" for 100% of the clubs below the top 7. This will mean less spending on building depth, and more spending on improving it. "Better to spend £25m on a first-teamer, and lose a squad player" mentality. We have a lot more to do, but that doesn't mean we can't. Only that maybe we should temper expectations over hope.
2. We are signing players nobody else above us wanted/targeted.
So that either means we all think good players are wanted by every club, or we are forgetting the obvious, that sometimes, signing more obscure players from clubs can hold better value to you than elsewhere. Nobody wanted the free-scoring Michu at the start of the season. Now look. Nobody else tried to sign Torres when we did. Nobody else was signing Xabi. Nobody wanted Mascherano. Nobody wanted Kagawa. That doesn't make them bad players.
There is one thing too. As I said before, we are looking to build squad depth, not improve it right now. Aspas, rated as a sub in the La Liga team of the year, was either over-looked by clubs above us, or aren't looking for player like him. We wouldn't be signing him if we could sign Cavani or Falcao, but that doesn't make him a bad player. I am not comparing them on quality. I am merely suggesting that we are looking for value, because we can't spend uber big on signings. If I listed the squads of all the teams above us, many of them came in for under £10m. This dillusion that they "can't" be good because they're cheaper doesn't hold truth. You pay for past success, not potential suitability or contribution.
3. We aren't a big enough club - living off our history.
There will always be doubts about teams whose recent successes are a shade on their past. We are not as feared or as good as we were as a club 20 years ago. 99% of people would agree that we are less competitive and unlikely to win the league. That doesn't mean we aren't big enough to compete at a higher level than our current position, or else nobody would over/under-achieve. As suggested by many, our profit margins are better than our league position comparably, and there are teams above us that continue to under-perform year on year, another that has over-took us as much down to our poor investments, as their very good, and a team that is willing to spend, but overly frugal. Why is it unrealistic to think they'll continue in the same vein? Its less realistic to think they won't?! Arsenal have money and a manager scared to spend (the same for more than 5 years), Spurs have a very good manager whos signings have had mixed success (1 year at the club) and an owner who doesn't like big spending (3/4 years), and Everton, a team whose squad depth has been their weakness, and most obvious thing holding them back from better exploits on the field. (Last 4 years). Why conceive them as any different now!?! I'm not comparing us to the top 3 because it is obvious they are at the moment, too far away for one seasons improvement to make them catchable.
I just want to add. Anybody comparing us to Swansea and West Brom is playing a game that some find humourous, and other humourless. I didn't realise one-season of success equated with levelling with a club that still (while most suggest under-performed) finished 10 pts higher. It makes no sense to suggest or compare us to them right now. There is no evidence we are level with them in terms of quality.
4. Signing top players would cost too much/expect more financially.
There is definitely an element of this that is true. We can't attract Falcao or Cavani right now. Nor could we afford it. The idea that we would have to pay a higher transfer fee is ridiculous, but we may well have to offer players better wage packets and bonuses to sign them. Sigurdsson did that to us, and look how valuable he has been to Spurs. Oh wait. He hasn't. The point I want to make, is there is much more expected of our scouting department right now. Not only to improve depth, but also to do so, while narrowing the gap to those above, while also improving the obvious weaknesses in our first XI. To do so with money-bags owners (easier to improve quickly) without, means obscurer talents, in-depth research and cleverness in approaching the right clubs willing to negotiate. It will be tough, and it is less likely than as been suggested by some, but it is far from impossible. Newcastle proved that, albeit short-term, the season before last.
5. We're signing works in progress - not Premier League calibre players.
Just because we are signing young players, doesn't make them improvements on what we have/incomparable to the same players at other clubs at the moment. Chicharito cost Utd less than £8m, and was young and had performed well in Mexico. Aspas is older, has experience in a higher quality league. That suggests not so. Mkhitaryan is 24, on the back of a record-breaking season, and will cost £22m if rumours are believed. You could compare him to Hazard, when he signed at Chelsea. Much higher price, for a less experienced player, who had impressed at a lower level league system abroad. We heard the name because of his reputation so close to Britain, not because he was known to everyone. You could even compare signing Toure to a player like Gallas when he moved to Spurs. He could continue to contribute at a top club, and his contract had ran down. Toure's wage demands are lower and of same age. So it could make sense for us to target him in the same vein.
Obviously I am just voicing my opinion on each of the things people have said, but I tried to apply as much logic and as objective a look on things as possible. I tried to draw examples to similarities to others. I am not saying everything I written should persuade you. I do hope you spend the time taking it point by point though. I'd sure like to know what comes to mind, because you might help me realise I am wrong in thinking the way I do.