@AlexHokanson: “How can I tell if a bike can handle my weight in the future? I found this bike at the LBS and they didn’t mention anything about this not being able to handle my weight…”
This is a very deep rabbit hole to go down. However, 90% of the people that buy mountain bikes in the US at roughest may ride down a dirt road. Your Speshy, while a number of notches up from a department store bike was not designed with your riding efforts (poor 180s, endos, roosting and 200lbs of rider) in mind. I don’t believe the bike shop steered you in the wrong direction, because they honestly rarely know what how anyone rides. Most people are not honest with themselves either thinking they can get a lower cost rig and it will perform the same as something more expensive. Once in awhile you’ll will come across bikes that punch above their price point, but this is the exception and not the rule. The moral of the story is to go for sturdy and durable.
@AlexHokanson: “They always say that bikes generally just won’t be able to handle the lateral pressure of landing sideways on the bike from endos and 180s, especially with the larger sized wheels.”
Your bike shop is correct here. The larger the wheel diameter, the more flexible the wheel will be. The exceptions to this are more expensive or really heavy, but there is a reason BMX bikes run 20″ wheels. 29er bikes have only begun to be used for aggressive riding in the last half dozen years. Prior to this they were the domain of cross country bikes. As such, you are not going to find many low cost heavy-duty 29er bikes.
Back to your conundrum of rad-getting on a bike on less than rad built wheels. Your least expensive option which may still run you $200-300 would be to have your lbs build you more sturdy wheels (new rims, spokes and use your hubs). You could just do the rear wheel too. If you stick with it then do your research for your next bike. Party.