How much to put down for house deposit?

In very lucky position - have managed to save up 100k over the last 9 years - now looking at buying a house with partner, combined we bring in about 80k. But currently I’d be putting in most of the deposit, partner putting in 10k.

Price range for houses is around 350-400k. Interest rates are over 4% right now, should I use most of my savings for the deposit in order to have less of a mortgage? Or would it be wise to leave more of a cushion?