The question of buying a new striker this summer makes no debate, as everybody agree that Arsenal needs more and better offensive players. Still, a few questions need to be answered about that.
Olivier Giroud currently plays as a target striker, where is main role is to hold the ball upfield, make deflections for his wingers, and conclude actions. He is not asked to make runs behind the defenders like a pure striker even if it adds more options to Arsenal. When he does, on counter attacks, it brings goal opportunities like his double miss against Tim Krul, pushed in the back of the net by Mesut Özil. More and more, his integration in the collective has made his passes better, despite some unfortunate touches. We can overall say that he has made a good season despite what is being said about him, especially given the scandal he had been through.
Though, we can also arguably say that he is reaching his ceiling given his age and his potential. His finishing remains his main flaw, and his header game is way under-effective for a player of his size. With wingers and offensive midfielders in great shape, he is doing a good job as target striker, by fighting with the defenders and passing the ball in one touch to his team mates. Overall, we can't really expect more from him.
What could make the team better ? Arsenal needs a target striker in order to allow the wingers to make runs behind the defenders and to be at the reception of through passes or crosses. This is precisely the part of the game where Giroud mainly disappoints : finishing and positioning.
What are the alternatives ? In the team, Sanogo, Podolski and Walcott present the best profiles. According to me, Sanogo has a way more better scoring instinct than Giroud, with a much higher potential. His performance against Liverpool in FA Cup was particularly remarkable, where he spent the game grappling with Daniel Agger and drawing defenders attention by his runs and contests on every ball. That being said, there is a lot of room for improvement. First, his integration within the team is not done yet and he will obviously be more effective once he will know his team mates better, and his team mates will know him better as well. Then, by playing and scoring his first goals in the league, he will know how to play, create space and fit into the Wenger's gameplan. He already showed some good things, now patience and gradual game time is the key.
But for now, Podolski seems to be a more effective solution than Yaya Sanogo. He showed his qualities of striker a few times this season and his finishing is a huge quality. Still, it is hard to judge his production as a target striker as Arsène Wenger prefers to use him as a wide forward. If he does so, it is probable because Lukas Podolski would be struggling too much in this central role, and the team would lose the benefit of having a clinical winger.
Finally, Theo Walcott is probably the more gifted offensive player in the Gunner's squad. He is arguably the fastest player upfront, with a dreamy combination of pace, precision and technique. Once again, the question we can ask ourselves is where Walcott is the most effective : winger or target striker ? He proved to be a prolific striker as a center forward, but Arsenal could also use a real right winger instead of Santi Cazorla. This is for me the biggest challenge of Arsène Wenger : find the best combination offensively, while getting the best out of its players.
Don't get me wrong, I do think that Arsenal needs to buy a central forward. I just simply think that it is not our biggest concern. However, Josep Drmic would absolutely be an excellent addition to Arsenal, just because of the number of games Arsenal needs to play. We have seen that starting every games wore down Giroud and reduced his effectiveness. Following this idea, I think rotation upfront is the key more than looking for a way better striker. Starting a game with Giroud or Sanogo as target striker would not be a problem as long as our midfield and especially our wings are performant.
As a result, the main objective for Wenger during this transfer window, more than buying an ultra expensive striker, will be to strengthen its midfield and wings. As we've seen this year, accumulation of games and injuries weaken the team very quickly, particularly in midfield. A team with Ramsey and Ozil or a team without them is not the same at all. I know this is an obvious fact but Arsenal can't afford losing so much because of injuries. No sports team in the world is as much effective with or without its key players, but we have got to limit the damages. According to me, the wings is the area where Arsenal is the weakest, with only a couple of pure wide players in its squad (Podolski, Walcott). I think this is the spot where Arsenal needs some fresh legs. One or two more players able to play on the wings would be a valuable addition.
To conclude, I would say that Arsenal need to bring in a winger and a striker (a striker also able to play on the wing would be perfect). Of course, this is only for the needs forward, because replacing Bacary Sagna is for me the more urgent problem. And believe me, you won't find a better cast than Serge Aurier for this role. But this is another debate...