I rode the section of the trail from Richmond to Gaston over two days - essentially, all except the part above the gap to the north. It's a really good trail, but there are just enough shortcomings that I hesitate to put it at 5 stars, particularly compared to trails I've been on in West Virginia and Pennsylvania earlier in the year.

First, I'll note that I didn't notice any pig farms, despite expecting to on the southern section, nor any Rottweilers. There were some cow farms and a horse farm, but the only hazard were the many walnuts on the trail. I did see two cats, a lot of chipmunks, and quite a few blue jays, though ironically not a single cardinal.

The scenery is mostly fairly narrow wooded areas, with farms on the other side, though there are a few areas of denser wooded areas, notably by the nature preserve south of Muncie. This can be pretty, but it's also only partially shaded, and the afternoon sun slices through the trees pretty effectively. If you're doing a longer section, I recommend going northwest in the morning, and southeast in the afternoon if possible. I was going northwest and west in the afternoon of the first day, and the sun was doing an admirable job of trying to blind my left eye.

Amenities are good, but just short of great. There are restrooms every 4-5 miles, most of them with hand sanitizer, which is quite good. There are a decent number of water fountains as well, but of the three I tried on the northern section, two smelled bad, and one (by the Hitching Post, technically off of the White River Greenway but close to the Cardinal Greenway) didn't work. The southern section was reliable in this area. Outside of Muncie, there aren't a lot of places to pick up water in the northern section either, so err on the side of packing more water than you'll need.

The trail condition is generally very good, though it can be a bit bumpy in spots in Muncie. McGalliard Road is a more highly trafficked road crossing than most trails have, but it has an island in the center so you only need half of it to be clear at a time. I recommend jogging the bike across halfway at a time if it's a busier time of day.

The elevation gain is not negligible. Including segments on the White River Greenway in Muncie, and the Whitewater Gorge Trail in Richmond, I logged over 2000 feet of elevation gain, and it was noticeable, especially on the southern section where there were moderate, but extended, hill climbs. By comparison, I logged less than 1200 feet of elevation gain on the Greenbrier Trail in West Virginia, which is also longer. So don't assume that because it's in Indiana, you won't have some decent climbs!

I also should note that it's worth going into town in Muncie, whether that's the White River Greenway, which intersects with the Cardinal Greenway in two places, or grabbing some food at some of the excellent restaurants or breweries downtown, which is easily accessible from the trail. I always try to find a cool town or city to serve as a base when exploring a new trail, and Muncie did a great job in that regard.

Got 6 miles in starting by Muncie.
This portion of the trail is just as the other couple parts I've experienced.
The paved trail is mostly flat, level and equally shaded/open.
The one thing to be aware of is a couple bad spots/cracks in the pavement that could result in an ankle injury or biking issue, but this should not deter one from using the trail.
So as always, if in the area and want to get a couple miles in, this should do.