The first thing I'd suggest is changing your Synthesizer to the Microsoft One Core Voices and try selecting from among those. The selection is wider and, if you elect to install any of a number of variants on English (UK, Australia, Canada) in addition to US (and I'm presuming US is your home country - tweak the prior list accordingly if it's not) you get quite a few more. You may find something/someone you like.
I can't speak to latency issues with character and word echoing as I just don't pay that much attention to that in most cases. It could be just as bad with One Core, but I don't know that for sure.
Brian - Windows 10 Home, 64-Bit, Version 1803, Build 17134
Explanations exist; they have existed for all time; there is always a well-known solution to every human problem — neat, plausible, and wrong.
~ H.L. Mencken, AKA The Sage of Baltimore