With the amount of money we have I'd say 4th is about par - Utd, Chelsea and City all have more money than us.
But with the amount of money clubs like Spurs and Liverpool have spent to try and unseat us in the top 4 I don't think staying above them has been as easy a task as you're making out.
The last couple of seasons haven’t been easy and we’ve spent money to stay in the race but I get the impression you’re thinking of the Prem in its current state as if it was like this after we left Highbury. In fact, it’s as if your forgetting we were Champions. Take City and their billions out of the equation because they weren’t around. Liverpool had a top 4 team around those times under Rafa but they were never a threat to us like Man City are now. Do you really think Spurs under Martin Jol should have been pushing Wenger to his limits? Or Everton and Villa in those years? No way should it have been a possibility for us to have dropped out of the top 4 and been a mid-table team. Be serious.
Back to the original theme of the thread, I'm happy enough to keep Wenger on for a bit longer - the man may have his flaws as a tactician, but if he can sell off his best players every summer, and start each season with a bunch of bargain-basement misfits and youth players, and still manage to finish 4th (behind 3 of the richest clubs on the planet), then I have no problem with seeing what he can do each year with a settled squad and serious money to strengthen it with (even if it turns out someone else is forcing him to do the spending). I also think that a lot of the little things we've been grumbling about for years have started to be quietly addressed, so I'm prepared to give him a bit of credit for that too - the coaching team has been refreshed, we seem to be giving a bit more thought to the defensive side of our game now, the attitude of the players looks better, contracts renewals are getting sorted out earlier, the dead wood is steadily being cleared, and big money is starting to be spent on top players. We've even started getting more British players in the squad (for anyone who ever gave much of a toss about that to begin with)! All positive little signs that things are maybe starting to change for the better.
That being said, I'm nowhere near as worried about losing him as I have been over the last 8 years, when everything's been so tight. As a club, we're now in a pretty good position - the academy takes care of itself, we have a new team of executives and suits to take care of the business side of things (although they could still do with another couple of windows to practice transfer negotiations!), and there's large sums of sustainable money coming in each year - so whoever eventually takes over from him really shouldn't have anything to worry about other than training the first team. That really does open up the pool of candidates we can at, and the new revenues give us a bit of a safety net if we make the wrong appointment (we should be able to survive without CL football for a bit if the worst happens now)...
The originally move from Highbury to the Emirates was for the purpose of competing with clubs like Man Utd and Real Madrid. Not staying in the Top 4. Gazidis has come back out to realign that vision when speaking about Bayern and Dortmund. Some fans are getting it twisted.