First and foremost, welcome to LRH! I think you will be able to find most any answer that you are looking for in regards to firearms, shooting, and hunting. Just remember that all answers given are opinion and we do have professional builders and ballistics guru's that really know their stuff. With that said here are my ideas.
I like that you are going the route of the 25-06. It is a great overall caliber to about 700+ yards given the right load. The only issue with the 25-06 is the lack of high ballistic coefficient bullets to really allow it to stretch it out. However with the laser like speeds you can get the bullets up too, with practice will allow you to really reach out there. 200 to 300 yards is pretty much point and shoot with that caliber barring 20+ mph winds.
I am an avid Savage fan. They have some great rifles in the LRH category. In my opinion the Mod 111 LRH with the accu-trigger and accu-stock will provide a great platform for your long range needs. It comes with a fully aluminum bedding block that extends into the forearm for rigidity. It also gives you a muzzle break that can be turned on for bench shooting and off for field use to protect your ears a little. This model also comes with an adjustable cheek rest. I believe this to be a total package that is well worth the cost. It is however cheaper than the Sendero by quite a bit. This is an advantage because it will allow for more money to be put toward your optics.
Bullets are very subjective. My one buddy has a the Savage Mod 110fp. It shoots lights out with just about anything you feed through it. He is currently loading the 75grn Hornady V-max for maximum carnage. He is also loading with 120grn Sierra Game Kings for deer. I have had really good luck with the 120's when I was still shooting the 25-06 for whitetail deer. It was a Howa M1500 which is a very good rifle with a little bit of smithing (tuned trigger, bedding). You probably want to stay right around in the 75 to 115 grain weight for coyote and deer. The heavier for the deer.
Make sure you consider a good scope. My suggestions lie in Nikon, Sightron, and Vortex. Bushnell Elite 3200, and 4200 tactical models work exceptionally well for the money. I currently use Nikon Buckmaster 4.5-14x40 and 6-18x40 both with side focus. The 14x has a mil-dot reticule and the 18x has a target dot for seeing groundhogs out past 1K yards. The Vortex Viper series and the new PST are getting great reviews and more than likely my next purchase. Sightron has been getting rave reviews of there SIII and should be on the consider list.
Many are going to support you on your decision for the Sendero. It is one of Remington top rifles. It is a shooter, but I am a guy on a budget and it has been my experience that for the money saved buying the Savage you just can't beat it. Good shopping and I want to hear the details of you decision and targets after purchase and set up.
Welcome to the addiction!
Tank
