What's your budget? I'd recommend an ASUS that is capable of the third-party firmware ASUS Merlin or DD-WRT. If you're not familiar with flashing a third-party firmware capable router, then eBay may have them already flashed. Just type in ASUS Merlin or DD-WRT. But if you go that route, I'd reflash it. It's not hard once it has already been flashed.
Many, many years ago I used a Linksys WRT54GL flashed with DD-WRT and it was pretty stable. To this day I still own this router and could use it if I wanted. The current router I have now is an ASUS flashed with ASUS Merlin.
It's very important you keep your router firmware updated or use third-party firmware and keep it updated as well. Routers can be hacked and turned into a zombie botnet. It's also important to change the default username and password, don't allow remote administration, turn off UPnP, and if possible don't use port forwarding.
I solve my port forwarding issue in a very clever way using a local Team Speak server install. In ASUS Merlin or even DD-WRT you can setup a VPN inside the router using OpenVPN. So I set that up and when I need access to my Team Speak server I use the OpenVPN App in my phone, make the connection and then fire up the Team Speak App and make a connection. Since when I made the VPN connection to my router it's like I'm making a local connection as if I was there. So if you have to port forward for yourself this may be a solution. Now of course you'd think the VPN in the router would make an open port, and I guess it does, but it doesn't show open at all. It's like hidden. I tested my IP with open port scanning websites like Shodan, Censys, GRC's Shields Up and nothing found. I even ran an Nmap scan using my paid-for VPN to give me an external in and no open port found. And to take it up a notch I even tried with a so-called magic string for OpenVPN and still no discovered open port. So I asked about this at the OpenVPN forum and only one person responded and just said OpenVPN was smart enough to stay hidden. So I asked for him to elaborate and he didn't. My guess is that the magic string I used to find this open port is different from what I had. I have no idea.
Anyway, if the grand daddy of them all Shodan and/or Censys doesn't show it, you're pretty good. A typical open port via port forwarding can be pried open.
