Website for a small management consultancy start-up

I would like a website built:
6 Main pages: Home, About, Services, Insights, Contact
Sub pages: Services - 8 services listed with own page linked
Social media links/feeds
Possibly video embedded (or potential to add at later date)

* Should be business-like, clean & clear...not messy or confusing, good use of colour and imagery
* I need easy access to change text, add articles/insights & link them to service pages
* It needs to function on web/mobile - all platforms
* rotating images and straplines
* Good optimisation: SEO, integrated analytics, keywords etc etc

I have built an outline site on WIX but it is pretty bad and doesn't do the job - I am hapy for it to replace this in WIC if appropriate or start again on another platform.

I have lots of websites I can give that demonstrate the feel and approach I like