Flick, I hope you are built like a s**t brick house. For me, what you have described is my heavy gun
Of course, any combo can be made to work but for me, a light gun is something that I don't mind carrying in any terrain I hunt all day. This also means that shots can be reasonably close (inside 500yds). I hunt mule deer and moose and for me my light gun is a 30-06. I am about to build another stock for it to lower weight another lb or two. I am shooting for 7lbs complete.
The 6.5 wildcat will work but is very hard on throats and will heat up your barrel in no time so varmint hunting is limited to three or four shots. This is also a lot of gun for deer inside 500yds. That 30" barrel is going to be a royal pain if you plan any time in the bush.
If you like the 6.5, why not a 6.5-06 AI or the 6.5/284. With a 24" sporter barrel, you will get 3000fps with bullets that matter for deer and varmint weight bullets will push 3200fps. Easy on the shoulder and if you get a slightly thicker barrel, shot strings can be longer. This will be effective on deer to 700yds, if you can get the bullet into the boiler room, and varmints as far as you can see.
The rest of the components are up to you but for deer hunting, I would want a low end on my scope of 6X. Remember that deer can pop up a few yards from you and if you have too high a mag, all you are going to see is a brown blurr. Adj. objectives are also a pain in a hunting/walking situation. My scope is a B&L 2.5 X 10 with turrents. I usually leave it at 6X. This helped me connect on a large running mule deer last weekend. There would have been no time to adjust the scope in any way. This was a "big deer", take off safety, good sight picture with follow through offhand shot.
A 15lb rig would have been impossible to put into play that fast. I am building a "heavy" gun in a 30 Gibbs which will spend more time on portable rests then moving. This rifle will have a higher mag scope (6X24 B&L 4000) and will be used mostly for LR hunting in clear cuts. I am guessing weight around 10lbs. Barrel 26" with a 2" muzzle brake. Will be used on Mule deer, moose, black bear inside 850yds.
Consider the most difficult terrain/conditions you plan on hunting and build accordingly. I believe in keeping my hunting equipment as simple and as reliable as possible. In my area, the best hunting starts when the weather gets nasty and extra knobs, buttons and fiddly things just don't work when you are wet, cold, and your hands are a little frozen.
Have fun building your dream rifle. Take a look at the Rem 710 in 270. I think that this is one of the best designed rifles on the market today. Apparently is shoots too.
Good luck...
Jerry