wifi drops connection 5s

I have a 5S with 8.3 IOs on it. It seems with the last update that my Wifi isn't connecting as well at home or at work. When I get home from work it takes the phone quite a while to connect to Wifi sometimes I have to manually choose my Wifi. It's possible this could be due to my new modem/router from my ISP but I have no way of really checking that.

But the same thing happens at work now. That system hasn't changed. It seems like the connection isn't as strong. True I'm in a building where the signal has always been spotty but I know where I have a strong connection and it's not there anymore.

I have reset the network connections and it helped for 24 hours maybe. I've compared the wifi with my ipod which is still rocking 8.1 and the connection is much better with the ipod.

What I am asking after the long winded paragraphs is what is next? The restore which is what I'm trying to avoid. I love my carrier and had no problems with my phone until recently.

Thank you for any suggestions.