We have been doing SEO, SMO and PPC since one year for this company.
Regarding SEO on a high level, there are 10 keywords already on first page and other 5 keywords are in 3, 4, 5th pages. You need to improve the rankings of the keywords that has higher rankings and maintain/ improve the rankings of the top ranked keywords. You don't need to do any Keywords Analysis and on-page optimization. You need to do only off-page optimization.
Regarding SMO on a high level, we have been posting everyday one poster. Now you need to do only 4 posting in a week using the brand color and theme of the company. You need to have a good content writer and good graphic designer to do this activity. After posting, you need to increase the followers by sharing, tagging, etc.