Arsenal
Arsenal need to improve their attack, and make sure to score as many goals as the opportunities as they create. If Arsenal gets a good striker in the transfer chance and get reinforcements in some other positions in the team, their chances of doing very well in the champions league round of 16 more than they did in the group stages will be higher. I see Roma coming to the champions league next season, I see Mourinho as someone with a plan, they look to be on that track already to achieve that with their current position on the table.
It's no secret that Arsenal need a better central forward to strengthen the attacks. The ability to convert opportunities into goals is crucial, especially in high-stakes competitions like the Champions League. Other positions within the team have been well-balanced that just need to continue the developments. I think Arteta is aware of this situation, because their creativities have been wasted by the front line.
Roma potentially entering into the Champions League next season is something to hard to be true. They are struggling right now. But Mourinho is known for his strategic planning and the ability to build competitive teams. If they continue on this trajectory, securing a spot in the Champions League for the next season appears plausible. The upcoming transfer windows and the remainder of the current season will be crucial in determining their future trajectories.
Yes, Mikel Arteta must do something to improve his attack line because Arsenal current shortcoming are just that, the back line is quite good and stable but it also needs to be developed, before playing the match in the Champions League, Mikel Arteta should have thought about option for recruited strikers which can be relied on because the round of 16 is very important, especially since the opponent in the last 16 will be quite tough, so Arsenal must start prepare now before face this match.
Roma is currently in 6th place, which means that Roma potential to take part in the Champions League competition next season is still wide opens. But Roma needs to improved the team performance and Jose Mourinho has the ambition to be able to bring Roma to achieve good result because that is his dedication as a coach so far, he is very experienced so I thinks Roma still has a chances to get into the top 4 if they are more serious.