Well, I was in a similar situation. I have an iPad2 and am on Verizon (I do not have it connected to 3G though). While the iPad is great, its really too big to carry with us when we go places. Recently, we have been looking for a solution to watch our Slingbox while camping at races (we are Grand-Am fans) and for me to carry to work - Something smaller, but bigger than a phone.
I was immediately drawn to the 7" tablet size. My main test for size was whether or not i could place it in my coat pocket. (If I could "hide" it in a pocket, there was a much better chance that I would carry it with me more places). That limited me to 7" exclusively. After looking at the Original Galaxy tab on Verizon, HTC Evo View 4G on Sprint and Galaxy Tab Plus on T-Mobile, i decided to go with the Galaxy Tab Plus. I also looked at the XYBOARD 8.2", but it was even too big to fit in my pocket (plus Verizon doesnt have 4G in our area).
Ive only had it a week now, but since I have had it, I dont believe I have even picked up the iPad. While I knew that I would be liking the smaller size when traveling/camping, I didnt realize how much I enjoy the smaller size for reading in bed, or sitting on the couch... I am not bothered at all by how "small" a 7" screen is.
My only problem is with the carrier. While I am not thrilled at T-Mobile coverage, they DO have 4G in our area, and I am getting 6-8 Mb per sec download speeds, but it is EDGE/2G everywhere else. Had Verizon had a 4G tablet that was 7", i probably would have gone that route. But since you are wanting to use hotspot with a wifi-only GTab+, that wont matter to your situation!
Overall, I am MORE than satisfied with my choice of the GTab+. Since I wanted it to fit in a pocket, the 7.7" was likely too big, and I know that the 8.2" and up woudnt have met my needs for portability. I recommend it.
Edit: Due to coverage issues, I actually returned the Galaxy Tab Plus and bought a Moto Xyboard 8.2 on Verizon. I was surprised that it actually DOES fit in my coat pocket, but its close. as of now, i am actually liking the xyboard more at the moment.