First off, assists are not the same as goals. If one goes by the assists stats from last season, Gerrard was
the most creative player in the league, more creative than Silva and Suarez (according to
http://www.myfootballfacts.com/Premier_League_Combined_2013-14.html). And if one judges the creativity of attacking palyers mainly by the number of their assists, then Iniesta is an average player creativity wise, much worse than Gerrard. Gerrard and Rooney got many assists because they take well set pieces. Other than that they are not particularly creative. To say that Rooney is a world class creator of goals would be laughable. Rickie fecking Lambert assisted as many goals as Rooney.
Second, Rooney has scored 35 goals over the last two seasons - as many as Toure and Vidal. That's not a world class return. Costa for instance has scored 56 and outscored Rooney in both seasons, not just the last one. There are many attacking players who have been better than Rooney over the last 2 seasons: Ronaldo, Messi, Zlatan, Costa, Falcao, Müller, Cavani, Lewandowski, Suarez, Aguero, Robben, Ribery, Neymar, Bale, Benzema, Van Persie. Most of those players comfortably outscored Rooney or were much more creative than him. One could make the case about other players who don't have the reputation of being world class, e.g. Sturridge or even Dzeko (41 goals from just 54 starts for City). I haven't mentioned a player from Seria A, say from Juve, because I don't watch it but there could be other forwards who have done at least as well as Rooney
over the last 2 seasons, for instance Hazard - another player who would be a much more attractive signing than Rooney, or Mata. Or Higuain. Don't know. But to think that Rooney was one of the best 10 attacking players over the last 2 seasons would be pure fanboism.
The fanboys argument may come sometimes from fans of other players but also from fans who don't bye the hype.
Edit: Just checked Higuains stats: he contributed 62 goals over the last two seasons (goals + assists).
Benzema: 78 goals! (44 goals and 34 assists)
Mandzukic: 48 (only goals)
Lewandowski: 64 (only goals)
So, some details.
Your post is extremely inconsistent and lacks logic. You start of saying that assists should not(
edited) be considered same as goals, yet after that you name Robben and Rivery who hardy outscored Rooney. And actually their scoring return is average at best. It's very odd and sort of defeats any purpose. It either one, or another. As for set piece i think it's very stupid not to count them or say they are in any way irrelevant. A lot of goals are score from set pieces, without players with great delivery skills like Gerrard and Rooney these goals would just not happen. It' extremely important to have players, that can take set pieces at top level. And both finalist of CL prove my point to a T. With all the attacking threat of Real it was their set pieces that made the key difference. With Munich and in the final.
Rooney did not score as many goals over the last two seasons as a WC striker should, that is true enough, but it's also true, that he has not played in his favorite position up front. So to compare his scoring stats with a player that played CF-only is wrong.
This season Costa has scored 36 goals in 49 games (i cut two games where he played 20 min with injury), when Rooney played a CF, in 11-12, he scored 34 in 43 which is a better return. So clearly Rooney if used properly has the ability to outperform Costa.
Neymar inclusion is just stupid, he has only one season in Europe, he has big potential, but this year he has not delivered, it's a good enough first season, but that's it. His 15 goals in 41 matches is hardly impressive.
With some players you clearly suffer an extreme case of tunnel vision. You completely wipe out their last season in order to focus on more successive current one. City have been pretty great this year, they scored a lot goals and so on. But as good as they were this year, last season they were nothing special. And that includes Aguero, who managed just 17 goals in 40 games last season, Rooney had 16 in 37. So considering a huge gap in assists 4 for Aguero and 13 for Rooney, you can easily say that Rooney was much better than Aguero last year, even though it has not been a particularly good season for him as well. So if you consider both season their number in terms of assists and goals are pretty much the same, that 62 in 76(15 subs) matches for Aguero and
65 in 77(9 subs). So clearly Rooney has not been as bad as you try to make out.
That brings me to a next point, you've said that it's nothing special to outperform the likes of Welbeck. That's true, but that also is part of Rooney's problem actually. He is not playing with a players who is up to the level. It's a two way street, so Rooney should take some responsibility about our bad attacking shape, but not all. It's tougher to perform, when your partners are not that good. Obviously if MU had a solid CM, Rooney would not be shifted to a deeper role as much and could concentrate of attack. Robben and Ribery are two examples of a players that can be hardly called exceptional in terms of their goal, assist return, but they are vital part of a very strong team. Rooney was in that position himself, in 07-08 our main star was Ronaldo, but Rooney was a main part of that winning team and contributed to the tune of what Ribery produces for Munich. And actually i don't if you watched Munich games this term, but Ribery was pretty much average most of the season.
There are also some players that are considerably younger and emerging like Bale, Hazard, but remains to bee seen whether they can produce such a consistent performances as Rooney had. For example this year i've read that Rooney became the first and only premiership player that managed to produce double figures in both goals and assists in five premiership season. Obviously someone like Suarez just did not have enough "time", but the thing is there were stars in early 2000s in the Premier League, and they could not do it. So it's still a very impressive achievement.
I don't think Rooney is as great as Ronaldo or Messi, but i do believe he is a very good player who contributed heavily to our success, i also think that this season showed that he is not washed out or anything and still a very much potent force in the attack. I would rather keep him (provided that manager wants him and he is playing in a suitable role) than have the likes of Falcao, Benzema, Mandzukic, Higuain, Dzeko, Costa etc.
And as for how creative Rooney is, well free kick or not, i think it's very stupid not give Rooney a credit for his creativity, in the last 10 years he has assisted a lot goals and create a lot chances.