Did you repot the mugo this summer? If so, don't do any more pruning until about a year after when it was repotted. Got to give the tree time to grow.
I suggest getting half a dozen more mugo, so that you won't be tempted to over work the mugo you got.
Your tree looks "Flat" or 2 dimensional in that all the branches go to the 2 sides, with nothing coming forward or out backward.
I'm not great at "designing" from photos. Rather than style from photos, I'd rather see it in person, to make suggestions.
Right now it is winter in the CHicago area. This tree should be outside, in cold storage, enjoying its winter nap. Mugo pines have a definite need for at least 3 months of cold dormancy. Growth will decline if this tree is deprived of its cold winter nap. My mugo is sitting, its pot on the ground in my back yard garden, with a few leaves piled around the pot. No other protection from the cold. Your tree should be out there too. If it has been indoors for more than a few hours, don't put it out tonight, we are supposed to get quite cold. Wait until the weekend when the daytime high will hit 40 F. Then put the tree outside, and let it stay out.
IT takes about 2 months to fully acclimate a tree to cold weather, where each night the temperature gets colder and colder. Bringing a tree indoors for more than 24 hours can undo much of the acquisition of cold hardiness. In winter it is important if you bring a tree in to work on, that you get it back out in the cold withing a few hours, or risk the tree being damaged by cold that it normally would have no trouble with.
The greater Chicago area has a very active bonsai scene. Attend a few bonsai club meetings, you don't have to join right away, see if you like the mix of people first. I think you would learn a bunch bringing this tree with you to visit someone. The options are the Midwest Bonsai Society meeting at the Chicago Botanic Garden, first Monday evening of the month, February thru November. There is also the Prairie State Bonsai Society that meets out at the Morton Arboretum in Lyle Illinois. There is Hidden Gardens Nursery in Willowbrook, IL. Jeff at Hidden Gardens offers classes and study groups, the the group classes and study groups are modestly priced, the individual classes are a little more expensive.
In addition there are at least 10 BNuts living in the Chicagoland area. I encourage them to reach out to you via the PM system that is part of BNut. I live in the Zion area, north of Gurnee, if that is geographically compatible with where you are at. I would not mind meeting sometime in the future to lend you some in person help with this tree. PM me for contact info if you are interested.
The Midwest Bonsai Society, based at the Chicago Botanic Garden, promotes public awareness, cultivation, and the living art of bonsai.
www.midwestbonsai.org
Winter Sihouette Exhibit Feburary 12, 2022 The 2nd annual PSBS Winter Silhouette Bonsai Exhibit is at Cantigny Park in Wheaton, IL. A Silhouette exhibit displays the bonsai without leaves and […]
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