We could and clearly should be looking at all the other forwards out there and compiling a list of players who are far, far, far better value for money than Falcao - thats if we didnt already put the go ahead on signing him when we first did the loan deal. Of course there are plenty of strikers who we could get for that money and would be better for us than Falcao can be, due to his age.
Examples? Lacazette would suit playing with the players we have in forward areas better and cost half as much. He's young has a very good scoring record and would add the much needed pace to our forward line. Then there's for example Benzema, we could entice Madrid for that money and he's in better form and less fitness concerns. Sanchez was available in the summer and for that amount of money we could clearly have got him instead, his speed and versatility would have suited us more - obviously he's not an option anymore, but he was available in the summer so who knows who is available next summer? He was good at Barcelona last season and they let him go. Likewise Di Maria at Madrid, the money made it happen and £44 million is a huge amount. Paco Alcacer at Valencia could obviously be taken and for less than that price, he's a young man who will score lots of goals for club and country and can play his teammates in too. And this is all talking about forwards, in reality we have Van Persie still doing the business and Rooney can yet have his best seasons as a striker if he actually plays there. We could instead buy a top midfielder if we aren't happy with Ander playing Rooney's midfield role, then putting Rooney up front. And so on.
The options are many and almost all of them make more sense than signing Falcao, who may yet get back to his best but even if he does it'll be for a short time and for an astronomical fee.
Personally the only deal I'd have an interest in is if A) Before the end of the season he goes on a high scoring run for 10 games or so showing he's back at his best for a short time (which I'm hopeful he'll do whether we sign him or not) and then B) At the end of the season we say "No, that figure is far too high. Take him back Monaco and call us when you're willing to talk realistic numbers for a 29 year old" and they get back to us with a figure in the ballpark region of what we paid for RVP. If that call doesn't come and he goes off to a 2nd tier team in Spain (Valencia, Sevilla, etc) or something then so be it