Allow Only known IPs for SSL-VPN

We have around 450 users, lately we have been having an issue with brute force attack on our VPN. Would it be odd to ask end users for the home IP addresses to make an allow list, as well as request when someone is traveling and needs access to the VPN to shoot us an email and we add that IP address.

I'd say only half of our employees travel and when they do its usually to a retail chain store or a hotel and or coffee shop.

thanks for your comments in advance.