Nothing wrong with considering the standard 284 Win. With brass available from many sources it is still viable even though it was brought out in 1963. Imagine back then a rebated rim, minimum body taper and a 35 degree shoulder!
I have owned at least one and as many as three at the same time since early 80s. Have used a wide range of bullets from a 100 gr X to a 168 Berger VLD. Have taken quite a few elk, well over a dozen coues wt as well as many javelina, coyotes and jackrabbits.
Powder choices have changed over time as well. THE original load for Bob Hagel and IIRC was a 140 gr Nosler Partition with 57 or 58 gr of IMR 4350 velocity right around 3000 fps. H4350, RL-17 may be the best for hunting these days and H4831 with 180s is favored by the 1000 yd guys.
Melvin Forbes creator of the Ultralight Arms rifle said that the 284 win was the most popular cartridge for his model 20 rifle.
If there was an issue with the 284 Win it would be feeding but it can be resolved by a competent gunsmith. Some magazines are a bit on the short side but will still work. The Ultralight model 20 used a 3.1" magazine with usable space of approx. 3.050" I use a SA Ruger tang safety that was originally a 6mm Rem. It always fed the 284 Win perfectly. Around 15 years ago I had my gunsmith lengthen the mag box to a useable 3.050". Had a reamer made to my specs which included skim turning the necked up 6.5-284 Lapua brass for use with the 168 Berger VLD. Using RL-17 the 168's velocity is 2925 fps from a 24" barrel.
There is even Norma brass made in 284 Win, the owner of Grizzly Industrial had made specially for him. "It is double-drawn for body consistency and the heads are double-stamped for longer primer pocket life. This "special run" brass, created exclusively for Bullets.com, is produced to extremely high tolerances from high-grade raw materials."
http://bulletin.accurateshooter.com/2015/08/ultra-high-grade-norma-284-win-brass-now-available/
You can still find it at Bruno shooters supply in Phoenix.
https://www.brunoshooters.com/mm5/merchant.mvc?Screen=PROD&Product_Code=80953
I hate to mention it....you can also neck down the 6.5-284 Lapua brass to 6mm. I currently have two 6mm-284s which are IMO the best wildcat made from 284 win brass but that is another story.