I think Ramsey mcgree and archer would be good enough if we improved the defence.
The forward line karanka had was worse than the one he had first year. We just got even stingier in defence.
But yeah chuba would be a big big miss and as near to irreplaceable as you can get. We've waited 50 years for a striker to score as many as he did, and they're not like busses.
They would be ok, but McGree's an international and you're going to lose one for periods of injury, so we need a player as good as McGree as a backup basically, and someone better for a full strength side. Those three paying a lot of games would be good enough for play offs though, if we had other creativity, like giles etc, basically mirroring carrick's time.
I don't think you can do much about the defence, we're destined to ship a few with the way we play and the centre-backs are good when they're all fit.
The only real improvement I can see from last year at the back would be to swap out Smith, who doesn't really save us a great deal (could probably get a better defener), but he doesn't create much either. He's solid, but we wan't better than solid for that position, either a great denfender but more likely someone great goign forward. We need players better on the ball in this system, and good options both sides so would effectively want two players like Giles, tall order.
If we're even stronger going forward then the chances are other teams are more afraid, we get ahead faster or to 2-0 faster etc, it should stop teams trying to risk so much against us and they would likely score less. The opposition can't score when they don't have the ball etc.
I've only been watching since around 1990 but I don't think a lot of that ~33 years has been a striker problem though, I think it's been a creativity problem, the times when we've had both they've scored a decent amount (for the level we were at). Rav got 31 in all competitions when we went down, as he had Juninho. Yak, JFH and Viduka all had good returns, for the level of side we were, and what league we were in. It's rare for average prem sides to have a striker scoring a boat load. Most of the time in the Champo we've seriously lacked creativity, probably for 2/3rds of the years, or had poor strikers for 1/3rd. Under AK creativity wasn't bad, and the strikers were fairly good, but in that style no player was getting 20 goals for us, and 25 impossible. Some years we've had good strikers but not been defensive, just not played to the strikers strengths. Last year was a good axample of playing to a strikers strenghts, but not with chuba, with archer, his return for the games he played was excellent, but a key thing of it was when he wasn't scoring he had created space behind him for others to occupy, and chuba especially lapped that up.