One thing to be aware of if you buy a Tikka in 7mm Rem or 300WM and hand load, is that the relatively short magazine length really limits COAL, unless you want to single feed any of the heavy for calibre projectiles. They are fine for factory ammo but the real potential comes from hand loads loaded longer than SAMMI spec. I have a Tikka 270 running 140gr Sierra gamechangers
@3000fps and a Sako 85 300WM shooting 210gr bergers @2900fps, both >0.25MOA with hand loads. For the magnum I went with the Sako for the longer magazine. It sounds like your 30-06 is more than adequate if you pair it with the right projectile for the job and spend the time at the range, however, if you want a magnum go for it. Just beware of the Tikka mag length and slow twist rate before you buy.