In modern football it seems the manager in the dugout is always talking to their assistant/coaches because they are looking for specific feedback or maybe the assistant saw something that could be exploited. As such, your assistant manager should be a much more integral staff member in FM. Right now they are just a glorified automation tool; run training, set opposition instructions, pick the squad because I'm lazy. Hiring a good fit assistant manager should be the most important staffing duty. This can be reflected with specific feedback during matches which help you turn the tide of a game or help a player become more involved. And I realise there is already feedback from your assistant, but it is not up to scratch, it's usually too vague or just not helpful.
Most people I would guess play on "Key Highlights", so miss an incredible amount of match flow and it's very hard to tell exactly how the game is going unless you've had 30 shots to your opponents 0. In close games, a subtle change to a specific player instruction might be all it takes to swing the match in your favour. I have experimented with this myself by playing on "Comprehensive Highlights" to see more of the match flow and make changes depending on what I see. Just changing a BBM role to Mezzala or telling an Inside Forward to "Stay Wider" can result in you winning the game, you don't need to just up the tempo and pressing intensity as a default reaction to not winning. The point is, most players don't have time, or just don't want to play on anything more than "Key Highlights". That's where your assistant manager comes in, because they 'see' the whole game, and should know how the game is going.
If your right-back is on a 6.2 rating while the rest of the team is average, there should be feedback from your assistant manager on that player specifically as to why they are not playing well. Are they missing a lot of tackles and getting burned down the wing? Your assistant manager should be able to tell you that in some capacity. They would make the suggestion to add player instruction "Stay on Feet" and/or "Stay Wider". This means your right back is not less likely to dive in and get burned, but also they will stay wider so be closer to the opposition winger. Or if the opposition player is an Inside Forward, and you're being beaten inside, then "Sit Narrower" would be the suggestion.
If you're heavy favourites and you're relatively comfortable in a game versus a team who are sitting back but it's still 0-0, then your assistant should be able to alert you if there's a danger of being caught on the counter and what you could do to change it. If for example, the opposition seem to be playing quite direct and they have a pacey striker, your assistant should know this and be able to just give a reminder to be careful to not overcommit. Maybe to change your Full Back on 'Attack' to 'Defend' so you should have an extra man back when attacking, just small changes like that, which could be the difference in the win or loss.
They are your 'assistant' after all, so improving the ways in which they can assist you is surely a good idea because currently you can not have an assistant and really not notice it.
This is obviously just using one player position and match scenario as examples, but it would work with all positions and different match scenarios. And depending on your assistant's tactical knowledge, the suggestions will be better/worse/less/etc.
In modern football it seems the manager in the dugout is always talking to their assistant/coaches because they are looking for specific feedback or maybe the assistant saw something that could be exploited. As such, your assistant manager should be a much more integral staff member in FM. Right now they are just a glorified automation tool; run training, set opposition instructions, pick the squad because I'm lazy. Hiring a good fit assistant manager should be the most important staffing duty. This can be reflected with specific feedback during matches which help you turn the tide of a game or help a player become more involved. And I realise there is already feedback from your assistant, but it is not up to scratch, it's usually too vague or just not helpful. Most people I would guess play on "Key Highlights", so miss an incredible amount of match flow and it's very hard to tell exactly how the game is going unless you've had 30 shots to your opponents 0. In close games, a subtle change to a specific player instruction might be all it takes to swing the match in your favour. I have experimented with this myself by playing on "Comprehensive Highlights" to see more of the match flow and make changes depending on what I see. Just changing a BBM role to Mezzala or telling an Inside Forward to "Stay Wider" can result in you winning the game, you don't need to just up the tempo and pressing intensity as a default reaction to not winning. The point is, most players don't have time, or just don't want to play on anything more than "Key Highlights". That's where your assistant manager comes in, because they 'see' the whole game, and should know how the game is going. If your right-back is on a 6.2 rating while the rest of the team is average, there should be feedback from your assistant manager on that player specifically as to why they are not playing well. Are they missing a lot of tackles and getting burned down the wing? Your assistant manager should be able to tell you that in some capacity. They would make the suggestion to add player instruction "Stay on Feet" and/or "Stay Wider". This means your right back is not less likely to dive in and get burned, but also they will stay wider so be closer to the opposition winger. Or if the opposition player is an Inside Forward, and you're being beaten inside, then "Sit Narrower" would be the suggestion. If you're heavy favourites and you're relatively comfortable in a game versus a team who are sitting back but it's still 0-0, then your assistant should be able to alert you if there's a danger of being caught on the counter and what you could do to change it. If for example, the opposition seem to be playing quite direct and they have a pacey striker, your assistant should know this and be able to just give a reminder to be careful to not overcommit. Maybe to change your Full Back on 'Attack' to 'Defend' so you should have an extra man back when attacking, just small changes like that, which could be the difference in the win or loss. They are your 'assistant' after all, so improving the ways in which they can assist you is surely a good idea because currently you can not have an assistant and really not notice it. This is obviously just using one player position and match scenario as examples, but it would work with all positions and different match scenarios. And depending on your assistant's tactical knowledge, the suggestions will be better/worse/less/etc.