Reset my 6+ with new acct

Hello!

I have an iphone 6+. I have been having so many problems lately I was ready to run over the phone with my pickup.
I would ask siri to do something and there were these long delays, wrong answers, crackling when using bluetooth, couldn't find contacts or make calls without problems.
I was having many issues getting online.
Problems with the finger print features etc.......

I tried several things, that didn't help. Like resetting the phone several times etc. But when the phone was restored, whatever it was that was causing my problems was also restored.
The other day I backed up the phone, erased it completely and setup as a new account.

Now my phone works almost perfectly.

Of course I acted a bit out of desperation and didn't consider my purchased apps and most importantly, my 200g per month shared storage.

1, I wish to access the shared storage plan.

2, I do not want to have a restore of my previous account onto my phone.

It works pretty well right now and I don't want to screw that up.

Honestly, it was like my phone was hacked or something.
Maybe I should just change the password and log back on under the old acct.
I just don't want my phone to go back to acting like it did before.

Can some one offer any suggestions here?

Thank you in advance for your assistance!

Jeff