Danish oil is a varnish, meaning combo of seed oil and resin plus thinner. It's a great gunstock finish if you don't mind that it will build on the surface. It even does well on top of cured BLO to help see the grain plus add a little bit more surface protection. If you want to see the grain really well, like wearing 3D glasses, straight BLO or Tung oil for the first few applications (or for the whole finish process) is the only way to go. You can varnish over that, poly, whatever. I prefer to feel the wood surface rather than feeling a plastic coating on my stocks, so I use the penetrating natural oils that don't build up much, and sand them in to fill the grain.
Really, all this is a matter of personal preference and how much time is available to invest in the finish. This isn't a boat rifle so I don't care about waterproofing. I mainly want the grain to look good and it have a satin finish that's easily repairable and won't chip/flake, and since I have time to spend on it, BLO is the natural choice. Pure Tung oil is faster drying, but doesn't quite have the magic pop that BLO gives to grain. If you want a good finish, right now, wipe-on polyurethane is probably the best there is, three coats in a day and it's finished, but it covers up all that fine grain. I've finished cherrywood about every way there is (including French polish, that's another story) and for furniture I prefer just a mix of BLO, spar varnish, and naptha in thirds, over one coat of BLO sanded in and allowed to dry for weeks/months whatever before varnishing with the mix in multiple, light coats with a wet-sanding in between.