Get your self a decent modem with broadcom chipset plus a decent Dual Core Router which is highly compatible with Lede/OpenWRT.
I could recommend a Netgear R7800 for Lede/OpenWRT or a Linksys WRT1900ACS v2/WRT3200ACM but keep in mind the Marvel wifi driver for those Linksys devices is still a bit buggy at the moment...
In my opinion this is the best option and you will almost have endless opportunities... but LEDE/OpenWRT will probably cost you some time (depends on your needs and skills).
There are some great pre-compiled community builds avalible but you could also compile your own image with the packages you need.
For example i'm using the following stuff with LEDE at the moment: OpenVPN Client/Server, Selective VPN Routing, Selective UPNP, SQM-QoS, Adblock, Advanced Graphs/Stats and DNScrypt-Proxy... and im really happy !
A DSLstats compatible modem with a decent broadcom chipset (BCM63168/63138) shouldn't be hard to find... I would suggest to buy a used modem on ebay.
Personaly i would look for a DGA4130, this device should be even future proof for Super Vectoring (profile 35b), if Super Vectoring will be ever avalible in your area.
In my area Super Vectoring will be avalible mid 2018, so im quite happy that i bought a DGA4130 modem...