Written French does have all that inflectional morphology you talk about, but spoken French has much less--a lot of the inflectional suffixes are just not pronounced on most verbs (with the exception of a few, like être and aller--but at least 'be' in English is inflected in ways that other verbs are not). So there's not that much redundancy.

As for gender marking on adjectives--or nouns--it does almost no semantic work in French, except where you're talking about professional titles (doctor, professor...) that can be performed by men or by women.

If you want a heavily inflected language, you should look at something like Turkish, Finnish, Swahili, Quechua, Nahuatl, Inuit... Even Spanish (spoken or written) has more verbal inflection than spoken French.