Well since you're obviously into film, you should invest in a proper Dolby Atmos/DTS:X surround setup to give you options. You can either turn up the center channel, put it in "dialog" mode, or enable dynamic range compression (night mode).
Regardless, tou're not getting the full experience if you don't have a surround sound setup. Ideally you should buy a receiver and hand pick your component speakers, but even a sound bar is better than TV speakers, so long as it's from a well-known brand and has up firing drivers in both the front and rear. If the third number in the number of speakers is 4 or higher (ex 5.1.4), then you're good to go.
This applies to everybody reading this, not just lagoon8622. All your dialog problems are being caused by your TV speakers.
When HDMI came along and replaced DVI, I thought that would have finally been the end of video connectors that lock into the slot.
Thankfully I've been lucky enough to never actually own a monitor with a DisplayPort. They've all been HDMI-only. I currently don't need more than 4K 120Hz anyway so HDMI 2.0 is good enough. Probably won't upgrade again until we have 1000Hz displays (which is what's needed to completely eliminate motion blur).