We are a nation of tinkerers. Our attitude is that any good thing can be made better. I've improvised and modified a lot of farm equipment in my time, some of it for the better, some of it...well,we learn from our mistakes, right?
Beyond the "improvements" we inflict on machinery ourselves, there is a wide range of aftermarket accessories available for farm equipment. There are some accessories/add-ons that are brilliant ideas, that make machines work better or make them safer. Rock boxes that mount to the front of tractors are a good example of a good idea. Accessory steps that make it easier to get in and out of older tractors were a great idea. As long as add-ons improve safety or performance without compromising safety or machine durability, I"m all for them.
Then there are add-ons to farm equipment that live in a gray area. They add function or performance, and may or may not compromise safety or machine longevity. Grain tank extensions on combines are a good example. Modern combines are behemoths, engineered for specific axle and tire loads. Farmers universally add extensions to combine grain tanks, and as long as the extensions are within reason, there aren't many problems. But every fall you hear stories of broken wheel rims or broken axles, and if you explore the problem--surprise, surprise--the combine in question had a grain tank extension so tall it created problems for low-flying airplanes.
Similar issues result from adding triple rear wheels to tractors designed for dual rear wheels, dual wheels to self-propelled sprayers designed for "singles," and engine "repower" kits and computer chips for electronic diesel injection systems. Yes, the extra tires work, and I wish equipment manufacturers would design base machines to accommodate the extra flotation those accessories provide. Yes, it's nice to have the extra power provided by a "chipped" injection system. But when you consider the humongous extra load that aftermarket triples/duals put on axles, or the excess strain chipped engines put on drivetrains, there comes a point where the risk of major repairs trumps the benefits of the aftermarket parts.
Back in my younger days, I was enthusiastic about hopping-up motorcycles and cars to get more performance. Invariably, if I added headers or tinkered with carburetors or changed gearing, it created a chain reaction of problems. More power caused transmission problems. Changes in suspension affected tire wear. Headers and open exhausts resulted in conversations with the local police. Eventually, I wearied of dealing with the consequences of my tinkering, and now leave my vehicles pretty much "stock."
I'm all for add-ons that tweak machinery for more safety or more convenience. I'm "okay" with stretching engineered designs. I'm uncomfortable exceeding engineered design parameters. And that's my opinion, subject to change and frequently questioned by those who know me well.