Why does my moto G from US Cellular get poor signal now that I switch my plan from the $50 plan to the $60 plan

Cellular Signal Boosters / Repeaters

Your cellular carrier can provide you with a "signal booster" device that can repeat and boost a cellular signal you already get in your house. For example, if you consistently have one bar of coverage but no more at home, a booster can take that one bar and turn it into more bars. If you have one or two bars of coverage near a window but no coverage elsewhere in your home, a booster near that window can capture the signal and boost it, providing a strong signal throughout the rest of your home.
Some carriers offer such devices very inexpensively - $50 or maybe even free - especially if you're in an area where they know they know they have poor coverage. T-Mobile now offers such boosters for only a $25 deposit, which you can get back just by returning the booster to them.
Contact your carrier - or look at their website - to see just what they'll offer you and for how much.

Femtocells / Microcells

A femtocell - or "microcell" - is a small, low-power cellular base station that connects to the cellular network via your broadband Internet connection. Essentially, it's a small cellular signal tower that will provide a signal in and near your home, connecting to the larger mobile network over your Internet connection. This makes it ideal for situations where you don't even have a signal bar of coverage you can boost at home. The only "catch" is that your Internet connection must have a high enough download speed. Different carriers require different minimum speeds, but you should be fine as long as you have a solid broadband connection.
Ask your cellular carrier if they offer this sort of product and find out how much it will cost you. As with boosters and repeaters, a femtocell may be available at a steep discount from your carrier in areas they know they have poor cellular service.
You can also buy them easily on Amazon or almost any decent tech store - for instance the one pictured below works for AT&T and supports LTE (though it is a bit pricey), or you can get one that supports Verizon, T-Mobile, AT&T, Sprint, Cricket, and many others, but you won't get LTE support. Of course, since you likely have Wi-Fi in your house, LTE isn't really a big deal and the 3G will work just fine for calls and texts.
Editor's Note: For the official How-To Geek office we got a Samsung microcell device directly through Verizon, which wasn't cheap, and doesn't work all that well. And since it only works for Verizon, any of the people who come by who use other carriers have zero signal, which is really annoying. If we could do it over again, we'd have started with this zBoost microcell that supports virtually every cell provider and has many different models and options to choose from depending on the size of the house. They even have an optional antenna you can install on your roof to give cell coverage everywhere around your house. It's the best choice, and cheaper than most carriers will offer you.

Wi-Fi Calling and SMS

Wi-Fi calling is a feature you might remember from some years ago, but it's coming back with a vengeance. At the moment, in the US, only T-Mobile offers Wi-Fi calling for both Android phones and the iPhone. Sprint only offers Wi-Fi calling for select Android phones. AT&T and Verizon have announced plans to activate Wi-Fi calling in 2015.
Essentially, WI-Fi calling allows your smartphone to receive and place calls and communicate via text messages over a Wi-Fi network. Your home probably has Wi-Fi, so Wi-FI calling will let you use your existing wireless router instead of needing a new, specialized device. You can just improve your Wi-Fi signal strength, and all your devices will benefit!
Wi-Fi calling works transparently. When your phone is on Wi-Fi and has a poor cellular signal, it will connect to the Wi-Fi network and your phone calls and text will be sent and arrive over the Wi-Fi network. When you leave the Wi-Fi network, your phones and calls will be sent over the cellular network as usual. This is all designed to hand-off automatically, so you could start a phone call on your Wi-Fi network and your phone would automatically hand off to the cellular network as you walk out the door, with no interruptions.



WI-FI calling will also work on other WI-Fi networks, so it's helpful if you ever end up in another place where you have a poor cellular signal but have Wi-Fi. To use this, you'll need to ensure your phone has Wi-Fi calling support and that it's enabled. Android phones from T-Mobile and Sprint will often include this feature, so look up how to enable it on your specific model of Android phone.
The iPhone 6 has built-in Wi-Fi calling, although it currently only functions on T-Mobile. AT&T and Verizon plan to support it in 2015. To enable this feature on an iPhone, open the Settings screen, tap Phone, tap Wi-Fi Calling, and activate it.

WI-Fi calling seems to be the future goal the industry - T-Mobile, especially - is pushing towards. With Wi-Fi calling integrated into your phone, you don't need to buy a specialized device. Your home Wi-Fi router works. And, when you go somewhere else where you have a poor signal, all they need is a Wi-Fi network and you'll be able to get a phone calls and SMS messages through it.
Image Credit: Carl Lender on Flickr, Nan Palmero on Flickr, Wesley Fryer on Flickr

hope that helps

Freddy

Contact US Cellular. It shouldn't have anything to do with your plan.

Mark
Motorola Support

Phone signal does not depend on the plan amount, you might just get just bad reception, plan change was a coincidence.