Just want more simplistic catchy Death Metal with grooves. Slow heavy brutal riffs. I love Obituary,Autopsy, Bolt Thrower and Celtic Frost. Just not a fan of deathcore. Thanks.

Try Memoriam. It consists of members of Bolt Thrower and Benediction and started as a tribute band to the late drummer of Bolt Thrower (can't remember his name). Their full-length album "For the Fallen" is very solid.

If you haven't already listened to Bloodbath, that might work for you as well. I recommend their EP "Unblessing the Purity," which in my opinion is some of the best death metal has to offer, as well as their newest album "Grand Morbid Funeral." I would say the latter is more along the lines of old school death that you mention above.