I am drawn to birds of prey and medium to large mammals lol, dot real decisive huh?
I don't have a lot to add to what has been said. If time is an issue, i.e. you only have a limited amount of vacation time and your time at a given site is very limited, then the guide or tour could be a way to go.
If you have more time, you can go where the creatures congregate and wing it alone.
For example, Bald Eagles at Conowingo Dam in Marland and the dams between Davenport and Le Claire Il in the winter is a place where they congregate. Osprey all along the coastal and marsh areas in Florida (watch some of Mark Smith's videos. Perhaps contact him and see about booking an Osprey Outing with him).
Warblers and other small migrating birds in the Oak Harbor (McGee Marsh, Maumee Bay State Park) Ohio in the first 2 weeks of May
Yellowstone, Rocky Mountains National Park, Glacier all offer great wildlife opportunities.
Denali in Alaska, etc.
We spend 16 days in Alaska during summer of 2018, put about 3,000 miles on our rental car and got tons of wildlife and landscape. A friend of mine has been on at least 3 cruises to Alaska and he said many of the on-shoe cruise ship activities cater to photographers and the busses and vans will go to various hotspots around the ports of call. That may be a good option to you to combine a relaxing vacation with some wildlife and nature photography. Pat has captured some fantastic images while on his Alaska cruise adventures.
I don't know what your monetary situation is (and I'm not asking, it's none of my business) but guides and outfitters regardless of if fishing, hunting, back country adventures or photography can be pricy. However, if your time is limited or it is an area or a type of wildlife you're not familiar with then they can save you a lot of time wandering about and not seeing what you wanted to see.
If you have photographers locally ask around what they have done and recommendations. If you are on "Facebook" check to see if there are any photography groups for your area, join the group and start contributing. Most group admins will allow if not encourage people to ask questions. Some are post your photos only so you just have to be aware of the group rules.
If you see photos on a forum like this from someone's vacation especially if they were with some kind of group or tour, reach out to them and ask which tour group and if they had a positive experience. Many people would be happy to share positive or negative experiences with you if you ask kindly.
Wish I had a more specific recommendation. I think the medium to large mammals would be very doable. Deer, bears, bison, moose, elk, etc. Birds of prey, unless you're at one of the congregation points and in the right season are more hit or miss. In Alaska Bald Eagles were very common to the point by about day 8 I was only photographing ones in really pretty settings. They were that common. However, we only saw one Golden Eagle and I missed the shot.
Hope this is helpful. Best wishes on your vacation and I hope to see some beautiful images from it.
Jeff