Converting a road frame to a hybrid

[nammynake]

I have a Kinesis 4S road frame that I’d like to convert into a flat bar hybrid. It’ll also be converted to single speed and will only be used on gentle family rides on roads and very easy trails.

What considerations are there in terms of bar height and stem length? There is decent amount of steerer as I never cut it down originally. Oh, and suggestions on bar width ?

I assume I’d need something shorter than a road stem but maybe not as aggressive as a MTB, so maybe 70-80mm? It doesn’t need to handle amazingly but should be reasonably responsive and comfortable.

Thanks