Sidibe is technically a loan in.
I'm not sure we're good enough for fourth but I do think the signings we've made have improved us, even losing Gana and Zouma. I'm a little worried about a shaky back line, but I'm definitely hoping Mina takes a step forward this year as he gets consistent game time, and hopefully he'll even contribute some goals from the back. Gbamin and Delph are definitely a different style of player to Gana, who I rate very highly, but both seem to have the talent necessary to fill that hole.
Kean will be massive for us, I hope, and Iwobi is at least a little further along than Lookman was. Sidibe is a big improvement on Kenny as our replacement RB if Coleman goes down and does give Coleman some more competition. Add to that the fact that last year's signings have all had some time to bed in and play alongside each other and it's hard to see how we couldn't be at least a little better than last season.