So several things to add here but first and foremost you need to consider how you intend to hunt, standing or setting???
I stand while night hunting like most people do and I MUCH prefer a tripod with 2 leg sections. They are way faster to setup and less joints to get loose or mud to infiltrate. They are also more robust and stable because the leg sections are much larger in diameter. I also prefer the bottom section to slide OVER the top section, not many brands do this. This helps keeping mud and junk out of the joints or collecting on the other leg sections.
I run a 2vets QDT, its solid, my only gripe is the legs are traditional and the bottom section collapses inside the top section and I am continually retightening the bolts because I literally use it on hundreds of stands throughout the winter.
I would recommend a RRS, Fatboy (inverted legs), 2vets QDT, and the Leophoto SO362 Inverted Legs.
If you plan on setting down while hunting or want something that collapses down more you will want a multiple section tripod. Again the brands I would trust are in order depending on your budget. RRS, Fatboy, 2vets, Leophoto and also the Innorel RT90 on a budjet.
I've used/owned various heads and NOTHING is as solid as a leveling bowl, period. Unless you need an excessive amount of travel forget ball heads. I love RRS products but Leophoto makes good stuff on a budget, in particular the YB75LC.
As for the attachment to the rifle the Swiss Arca is the way to go IMO. A word of caution here however, I see guys cheap out and get the little plates that only have two Mloc screws going into the firearm. MAKE SURE you get an Mloc plate that attaches with at least 4 screws to the rifle and HAS STOPS ON BOTH ENDS.
Once you get your tripod, I recommend setting it up where your rifle is about level with the bottom of your sternum. Setting it up low like this allows you to shoulder your rifle on varying terrain. If the rifle lands perfectly in your shoulder on level ground while you are standing strait its TOO HIGH, trust me on this.
Once you find your sweet spot, mark each leg so you can easily set up and return to that exact height. I leave my tripod extended and ready to go. Breaking your tripod down between sets is a waste IMO and its noisy, adds wear and tear, and takes time in the dark. I pull up to a stand, park, pull out tripod and open the legs, attach the rifle and balance the whole rig on my shoulder and I'm gone! I can literally be gone from the truck in less than one minute and be completely silent. Breakdown to go to the next stand is just as fast.
Thats my experience and hopefully helps you to get started right the first time. Expect to end up around $400 and up, closer to 1k or more if you want something to last the next 25 years.