Before now arsenal have really spent enough money to sign young players in the the team, and will not make sense to spend huge amount of money again it will be of total waste for the club. The mistake Arteta made is signing so many young players in the club thinking that it will strengthen the team. Arsenal would have gone for experienced players too just like the kind of players Manchester City and Liverpool has. Having good, experienced players and talented one would have help the team alot .
But right now what arsenal just need is to go for a talented striker that will help the team to perform well, arsenal without a good striker I don't think they will be ending the season well.
IMO, It is not a total bad decision to sign those young players, for now, it might seem disturbing, but as time progresses and in the future when these young players must have blended and have got to understand each other's style of play perfectly, then you would see the positive impact of singing young players in a team. It is not late, Arsenal still can sign in experienced advanced players and to boost up the team should this become their problem.