I have to say that I really hated what they did with Google chat and Hangouts. I'll still use it for video chat but SMS got all jacked up. I downloaded Textra and it's been the perfect SMS chat tool for me.
I use Hangouts exclusively. I will never use anything else. I suppose you'll only appreciate it if you never text and used to use the old Google talk and old google messenger (from google+). Ever since society switched to the smartphone age, I find sms extremely archaic due to specific constraints. The old google talk app was super archaic so I find it strange that you don't like google hangouts. The old google chat had issues like group chat bugs, syncing the chat between web and mobile app version, and no attachments (photos). I use google voice to text and I haven't run across any text issues yet.
How do I prevent hangouts from importing my email history into my contacts? Every person I've ever emailed and possibly gotten email from in gmail gets put in my hangouts contacts list. I got multiple craigslist responses as contacts. I think this was the first thing to piss me off. I get hundreds of emails a day but I probably text less than 5 people and video chat with only one. To me it doesn't make sense to combine everything together in on big mess.
That contact list actually means nothing to me so I can't help you with that. I only use it when i need to compose a new message to someone I don't already have an open conversation with which is extremely rare. Otherwise, if I do use it, I'm not scrolling down that list. I start typing out their name and let the search find the contact.
Hangouts pulls your phone contact list. So it's already been merged, sync'd, and imported. Is this your first Android or the first time you noticed? Easiest fix (other than ignore): Manually prune Gmail on a PC Non-phone contacts move out of MY CONTACTS into another folder. Export as CSV. Remove google account from phone. Add Google account back, don't sync contacts. Import CSV. Sync contacts. *looks like Contacts is its own app now separate from Gmail. The phone contacts app should have a filter to remove contacts without a number in app settings.
If you have any email accounts set up, go into their settings and unchecked "sync contacts" If they're already merged into your contacts, it might take a bit more work
I'll check that out. I hand out my gmail address all the time but I forwarded my mail to yahoo years ago and never log in.