Sometimes it's a good idea to follow best practices. This is what we did by following the recommendations for "general-purpose servers with a variety of clients, recommended for almost all systems" from https://ssl-config.mozilla.org/.
With this, our services accept only TLS 1.2 connections and the latest elliptic curve ciphers. If your client or browser does not support these settings, it's definitely time for you to consider an update.
While we are looking for TLS 1.3 support, the openssl version on our systems (running currently Leap 15.1) does not support it - yet. Once there is an update, we'll let you know.