Diet Pi as a home router (WLAN, ETH),OpenVpn server ,Pi-Hole


I’m trying to configure my RPI2 as a home router plus Pi-Hole- i’m using DietPI but still now i was able to install only OpenVPN and setup RPI as router. I have additional WI-Fi and it’s works fine. My wan is eth and WLAN is LAN - when i try to install Pi-HOLE my system going unusable. Did anybody tried to achieve this before?
Also my configuration includes dhcpd, dropbear, hostapd, fail2ban, ftp server, apache, sql, PHP, ddns client (no-ip) but i want to improve it little bit more with Pi-Hole.