As Rick Nelson said, "You see, ya can't please everyone, so ya got to please yourself". Since you "really like the way the remington fits ... and the way the action is", then you might as well go ahead and buy one.
However, since you've asked for opinions I will provide mine, which is worth what you paid for it.
I don't think you are gaining anything switching to the 700. If you were starting from scratch it wouldn't be a terrible choice but already having the ATR you aren't gaining much of anything.
Yes, I agree.
Sounds like the Mossberg already does what you need it to do (including fitting you reasonably well), and that you simply want a higher quality rifle. Fair enough. However, the 700 SPS is itself built and sold as an "affordable" rifle, and offers no particular advantages over what you already have.
If you want to upgrade your equipment, I'd suggest saving up until you can afford something genuinely better (e.g. Browning, Sako, Weatherby Mk V ... there are plenty of options). Alternatively, if you're willing to buy secondhand (and why not?), you can already afford something better than a new 700 SPS.
sound decent or is an upgrade needed?
What you have is fine. And yes, 2 MOA accuracy is quite adequate for deer and hog hunting.
If you are keen on spending some money to improve what you have, rather than a new rifle I would replace the Butler Creek caps with
Leupold Aluminas. And if you like a bipod, a genuine Harris is better than a Stoney Creek imitation. Again, these upgrades are certainly
not necessary, just some things that you can think about if you're determined to make improvements to your gear.