To offer a fair and balanced view, potentially worse off as a result.
All of those could be a massive hit or they could be massive failures here. To remove a proven goalscorer and replace them with players who could be massive failures en mass would be far too big of a risk to guarantee success so to speak. That is not to say i wouldn't want us to take that risk, but benteke for example has stepped up a level and failed before going back down to relegation level teams. Dolberg could emulate Van Nistelroy/Suarez or he could emulate Kezman/Maccaroni. Sandro could well be a decent winger or could struggle with the change in leagues, the other lad Zeyich could be eriksen or could well be terrible.
My point is only that to offer a unbias view, we would not be stronger initially from making a deal such as that, and any strength we did develop would be both over a long term idea and the fact the majority of the players would have to adapt to a new league and step up in level as well. But as i mentioned i wouldn't be against the club taking such a risk as perhaps it is those sorts of risks we are needing to make to attempt to improve as a team overall.
Edit- i could well be getting maccaroni mixed up with another striker Boro bought. Alves was it? I can't remember now.