Would a small fluid based radiator plus a low speed fan be more efficient.  Our house growing up was hot water heated and quite efficient.  Also a friend of mine heats his small home with an electric oil filled radiator.  Certainly the wattage for a room heater is around the 900-1500W range, but I would think for the size of this gentleman's application it could be lower.  Though admittedly I've not yet run the numbers.

So oversaturation could result in damage to the circuit through blowby?

There are numerous ways of physically doing the job, but where homes are concerned there are certain regulations you should follow.  Most of them are not just nonsense legal crud either, they are for your safety as well.  When it comes to wiring in your home, you should always do it the right way; the safe way.  Always shutdown all power at the breaker/fuse box prior to opening or working on anything.  Double check with a standard tester that there is no power at the site you are working on.  If you don't have special equipment a small lamp is a reliable way to test as well, as far as outlets are concerned.  You should use properly rated wires, with the correct types of insulation (there is different codes as well as rating).  Conduit is often recommended for running wires, and surface mount is available (again check regional codes and regulations to ensure you are complying).  Use the correct types of electrical boxes and fixtures for your project as well.  Many Home Improvement centers will have knowledgeable individuals available to help you select the right components for your area.  If a lot of this sounds too involved for you wants, there are a variety of inexpensive LED type lights that are powered by batteries and are as easy to install as a few screws or even some adhesive and velcro.  If I can be of any further help, please feel free to ask.

I suspect, both software and hardware come into play as far as answering this is concerned.  If its a relatively "dumb" circuit, it may simply function as long as adequate power levels exist.  If its "pickier", it might want to register a certain predefined module that has particular attributes as far as the software is concerned.  Unrecognized modules may not function at all.  And again you may have trouble if the attached circuitry wasn't built to handle modifications.

When building and powering a solenoid, is more voltage/capacitance better for a strong fast field generation?  Or is it something of a balance between the two?  Secondly, how much does saturation come into play were the plunger portion is concerned?

I'd certainly like to know if there is one.

It will depend on the sensor you use as to the format of the feedback you receive and how it needs to be processed.  Also depends on what kind of data you want to collect.  What MCU are you using and what kind of data do you want to collect?

So you're not using a coil?

Any free software that recommend in particular?

What would you consider an optimal wattage for general usuage?

How large an electromagnet are you using?

I'd be curious to see this as well.

Why not build an AM radio receiver?

I could give you the physical specs of the coil, but I don't know its impedence.  What is the best way to determine it?