What I look for in an RV park is going to partly depend on its location, I also feel you should decide what sort of customer base you want to market towards (snow birds, contract workers, vacation travel, ...), and what point in the price market you want to aim for. I live in SW Louisiana about 20 miles from the Texas state line, so I know our area fairly well, other than the odd overnight stay I am probably not a person you would be marketing to.
I would say the number one thing I look for in an RV park or campground is peacefulness, site spacing helps with this, but so does the clientele and environment. By this I mean the long term resident pulling in at 3 am in his pickup truck with no mufflers can ruin everyone elses sleep, so can the saw mill 1/4 mile away with its shift change whistle and industrial noises. I am a part timer, spending typically 50-60 days per year on the road over the last couple of years, I can think of 4 or 5 times in the last year where my peacefulness / sleep was disturbed in campgrounds by inconsiderate neighbors. Three of those times were by long term residents with vehicles with loud exhaust, once was by someone that decided to pull into the space next to me in a tightly spaced campground and set up the outdoor entertainment center and watch some sporting event until after 11 pm with the whole family of 7 making noise less than 10 feet from the headboard of my bed.
As to the rest, wifi is nice, but as mentioned fast wifi can cost a fortune, its not like buying $50 per month high speed home internet, as it requires wifi infratstructure inside the park, as well as boat loads of internet bandwidth delivered to the park, which may not be cheap depending on if it is in town or not. Until a few years ago I was involved with a family business that had its distribution warehouse located about 10 miles outside a small city, as of 2013 we were paying a bit over $800 per month for 3 mbps commercial internet, by comparison at the time 20 mbps was available at my house in town for $80 per month. Sure this is a corner case, and lots of places can get commercial level internet for less. The problem is people want to stream video, and even a basic SD stream can take 3-4 mbps, and an hd stream can take over 10 mbps, multiply this by 50-60 people wanting to do this at once and you get into some serious bandwidth requirements. Also as more and more people move to bringing their own cell network 4G / 5G based MIFI internet the demand for campgrounds providing wifi may become partly a thing of the past, until I invested in my AT&T Mobley account last year, I too was concerned about campground wifi, these days I rarely even bother to connect to it, as I bring my own.
Now that I have said that, let me point you to a small campground I stayed at in east Texas a few months ago on my way to Fredericksburg, that I was very impressed with. http://www.lakelivingstonrvpark.com/ This place gets a lot of it right, from pricing to landscaping, to friendliness, though it has its faults, the spacing between sites is way too tight, and though what they have of public spaces is nice they could use more of them. The place also heavily caters to the snowbird crowd.
Ike
p.s. in the end I think my advice is to offer good amenities, opt for quality, not number, to me a functional air conditioned laundry room is way more important than a swimming pool, and only put in a swimming pool if you are going to invest the resources to maintain it and keep it sparkling clean. Common rooms, pavilions etc. seem nice, but I have almost never seen anyone use them, though I did stay at a nice little vacation destination rv park in Arkansas last week that seemed to get the socializing bit right, with Friday night outdoor movie night by the pool.
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