It's not clear from the question whether the context refers to the media industry, but if it does then 'valorisation de leur audience' actually means 'augmentant leur part du marché'.

dans une logique de valorisation de leur audience
-->
with a view to increasing their audience share

If it's not about the media, then 'market share' instead of 'audience share'.

A suggestion.

French term (edited): valorisation d\'audience

---> in order to improve their viewing figures (or ratings)

I also checked le grand robert & collins

Hello,

Can't "valoriser" mean "to increase" (develop)

Here, "to increase our audience with these services"???

I hope this helps.