i'm pretty experienced with 6.5-284's, and i'd have it any day of the week over the -06 version. it's a shorter round, doesn't require a long action, but possibly will if you're mag feeding, easier to get good brass, shorter powder column so should in theory be more accurate etc. etc.
my concerns would be that if you're wanting it to shoot heads around the 100grain mark as well as rounds around the 140grain mark, you're going to have a compromise in terms of throat length. in the ideal world, the junction between the diameter of the bullet and the start of the boat tail should sit just above the junction between the neck and the beginning of the shoulder. the 140's are a long vld style bullet...... if you throat for these, the 90-100's may well be hanging out of the neck of the case. conversely, if you throat for the shorter varmint rounds, your 140 vld's are going to have the shank of the bullet well down into the case below the neck which is not great for accuracy.
i use a 6.5-284 for everything and use 140grain amax's. get it throated for 140 amax or berger vld's and stick with that for everything. and don't let 1000yards be your limit either.........