Need expert advice for my FPL team

Hello Fantasy Steemians !! We are approaching the final third of the Premier League and Fantasy season, so I needed an expert opinion on how can I improve my squad and its performance. I have kept my personal target to finish in top 20 of a local league after starting poorly and place as low as 35th in a league of 45 people. Normally I tend to be in top 20% of any league in my previous 4 years, but this year has been a complete disaster except for last 3-4 weeks, where I have been able to jump up quite a bit.

However I need to up my ante and look to continue performing better, as I just cannot underestimate my fellow members.
Below is my team's snapshot ready for next gameweek.

I can snap up Jamie Vardy and Bobby Firmino for Aguero and Ayew (suggested as below)

in my forwards section considering Foxes' and Pool's easier run of fixtures compared to those of Manchester City, but then again, it is difficult to bet against Aguero's hot streak. However I guess he maybe rested once Gabriel Jesus arrives, which may be inevitable in coming 2-3 odd weeks making my case for Vardy and Firmino stronger. So it is just a dilemma I am under, whether to do the changes now or wait for 1-2 Weeks.

P.S - I have already used up my free transfer for next gameweek of getting Ben Davies of Spurs for not in form Otamendi. I also intend to loose Iwobi and Phil Jones in coming weeks, so can you also suggest a replacement for Phil Jones.
Cheers & Thanks in advance !! Please do follow me for more content.