Will a Barlow help? Well, if you buy an expensive one, yes. Cheap ones will only make the problem worse. You can either love Barlows or hate them--and if you try to buy one for under about $100, you'll hate them. The Celestron Ultima is of decent quality. The TeleVue Powermates, which are an improvement on the basic Barlow concept, are even better. Still, you'll get slightly better high-magnification views with an f/10 scope than with shorter focal ratios.
Although I have not used one personally, I understand that weight becomes a problem for the LXD55 mount with the 10-inch scope. This is just second-hand information.
Portability--now that's a complex question. German equatorial mounts are a bit awkward to move around. A 10-inch SCT is heavy. I'm a 45-year-old guy who needs a hip replacement. I can manage to put my 10-inch LX200 into the car by myself. One develops a system. The first few times I was afraid I'd dash it on the pavement, but I no longer fear that. The optical tube of a 10-inch Newt takes up a lot of space in your car but is not heavy to move.
For moving around your home, a set of JMI Wheely Bars is a miracle. You can move your scope (SCT or Schmidt-Newtonian) out of your garage and be observing in minutes, IF you are lucky enough to have room in the garage to leave it set up permanently.
You can get a 10-inch Dob much cheaper than you can get a similar SCT or even an Schmidt-Newt. Still, since I got my 10-inch LX200GPS, I find that I no longer use my 12.5-inch Dob (which of course has no tracking capabilities). I don't use it at all anymore. If you want deep-sky capability, aperture rules, but for planets it is less important, since atmospheric fuzz will limit resolution on many nights (depending on the night, the atmosphere stops any gain in resolution somewhere in the 8-to-14 inch range. On some nights aperture is important in that range, but on others not). For tracking planets in town, the extra aperture just doesn't make up for the wonders of an equatorial drive. The stability of the image and the convenience are major plusses for an equatorial drive over a Dob.
The two accessories you will want before any others, in my opinion, are:
1)Dew prevention, unless you go with the Dob, which has no optical surface close to the air except for the eyepiece (which can fog). The SCT and Schmidt-Newts will fog easily. Start with a cheap flexible dew shield and add expensive options later. Dew will be a problem in Iowa rather often (I spent 4 years in Mt. Vernon, IA going to college years ago).
2) An external power supply. The LX200 and LX90 scopes run on 12 volts. A cheap jump-start style battery will pay for itslef in the long run. Get one from Target, Wal Mart, etc, not from mail order.