Pros:
(1) Course design is excellent. Nothing too tricked up, but the layout is a good mix of holes, a majority of them that require navigating lightly wooded areas and modest elevation changes. Because of the variety and lack of redundancy, it is easy to close your eyes at the end of the day and bring up a mental slideshow of all the holes you had played earlier in the day.
(2) Decent mix of discs and throws required. This is due to the fact that on many holes you are given two or three throwing options. You can navigate the air left or right around the obstacles or alter the height of your throws lower or higher, for example, to go under or through branch openings of the large leafy hardwoods. If you are a traditional back-hand thrower, be it right- or left-handed, you'll do well on this layout to practice sidearm throws. Rollers are useful throws on several holes and long-range skip shots -- for example, on #11, off the out-of-bounds "lake" (asphalt surface of now unused parking space) -- can come in very handy as well.
(3) Excellent courses all need memorable holes. The signature hole for Riverside Park is obviously #10, the long downhiller from atop the start of what I trust is a sledding hill during the winter. (Apologies: I've never been here during the winter. Wish I had grown up across the street as a kid, though!) It's always good to have at least one crank-arm toss from the heights. Other above average holes, due to their challenge are the heavily tree-lined #6 (unless you have a Gorilla arm and can RH hyzer it over 350 feet), #11 over the asphalt out-of-bounds, #13 (downhiller to a hole that is fronted by an out-of-bounds footpath and backs up to a steep ledge that looks over the mighty Mississippi) and the #18 when the pin is placed far back in the trees.
(4) Tee pads are all cement and in very good condition. They are all aimed properly toward the general vicinity of the various pin placements.
(5) Course layout flow is excellent. The first 9 holes finish at the starting area, which makes a mid-round rest at the top of the hill possible. Hole #18 finishes about a 100 yards to the parking area and park building. Not too bad a distance as it allows a bit of recovery time (and to forget the bad shots of the completed round!) before heading out for another round or giving up for the day.
(6) High player traffic. While this could be viewed as a negative, I see it as a plus as it provides positive exposure to disc golf to those who come to Riverside Park for other purposes. The fact that the course is friendly to beginners and advanced players alike is a big positive. It is an excellent course to introduce novices to the sport as it will provide them with an appropriate dose of enjoyment and challenge, absent the kind of frustrations that could be experienced by a beginner on an overly tight course with tall weeds and other hazards in which discs can be easily lost.
(7) Two practice baskets by the starting area.
Cons:
As this is a very good course, there are not many areas for improvement that come to mind. Yet the following factors -- admittedly nit-picky -- prodded me to lean toward a "4" rating rather than a "4.5." If there were a way to do a 4.25 star-rating, I would have.
-- Length. Riverside Park is basically a par 3 DG layout for the advanced level players. This point is both a "plus" and a "minus." It is a plus for those in the beginner to intermediate stage of developing their DG skills. It's a great course for those new to the sport to practice and advance their skill level, so for them I'd be tempted to rate the course a 4.5. The following comment, therefore, pertains mostly for those a bit more advanced in their play levels: While some of the holes were noted on the signs as a par 4, there are not any "championship" par 4s - i.e. holes that require two long throws. The longest hole (#5) demands a long drive, but in a wide open area to a slightly less open landing area. For those able to throw over 300 feet, it is an easy 3 and for those who throw upwards of 400 or more feet (not me!), I'm sure it is not too unusual to post a 2.
-- Signage. This is another "plus" and "minus" aspect of the course. The durability of the metal signs and the seeming accuracy of the distances noted to the various pin placements are both plusses. But for the player navigating the course for the first time, it would be nice to have signs with clearer lettering that you don't need to bend down and squint to see. The quality of signage is always a moot point for regulars who know the course inside and out, but for aesthetic reasons as well, it would be a nice touch to have slightly more colorful signs with larger and easier-to-read lettering.
Other Thoughts:
I suppose I could place the following comment in the Con section, but I think it relates to more of a personal preference of mine. For this reason, I'll post these comments as "neutral" ones in this section:
Except for the hilltop drive from the #10 tee pad, Riverside lacks a bit of the OMG factor. It adds a bit of excitement to face a few "oh my god, now what do I do?" situations during the course of a round. But overall, that's not what Riverside is about. Rather, it is a fairly straight-forward layout --without too many surprises -- that offers enough of a challenge to keep you coming back for more.
All that said, I'll still share my slight bias: In order for a course to rank as truly exceptional, I enjoy having a few holes where I'd like to experience, at least to some extent, that risk-reward, heart-racing sensation of threading the needle through a tightly wooded area or the worrisome decision about not under-throwing or over-throwing a drive due to penalizing hazards or out-of-bound areas. On these two points, I would admit that #6 modestly covers the first variety of heart-rate-raising challenge (thread the needle) and #13 covers the second variety (critically important distance control). #6, as regulars well know, is rather heavily wooded, but there's always the safe option to throw a RH hyzer to the far right into the clearing for a relatively open approach. #13 does get the juices going since it is so tempting to go for the birdie, but here again, there is the safe option - that is, to lay up in front of the footpath and go for the sure par "3" rather than go for broke on the drive and risk the chance of your fave plastic platter going down the slippery ledge toward the Mississippi.
In other words, unless I'm trying to birdie #13, there are no holes that cause a fear of potential doom, thus getting my heart racing too heavily. Given my mid-50's age, maybe that's a good thing.