I'm not sure you've thought about the costs and noise associated with cheap space heaters.
When I compare the amount of heat generated by an antminer S1, drawing under 500W, and the about provided by a quiet alternative, an oil radiator, at 1500W....A great many of the space heaters you'll see used in economically disadvantaged homes are ancient radiant heaters that consume 1500W constantly, and are loud as hell. The miner puts out many many more BTUs per hr per watt. I do not have the specific data, but I can assure you it takes less wattage to heat our homes.
If you consider the amount of $ spent to heat the home, you'll see that the mining gear need not be "profitable" to achieve a net gain for all the parties involved. It only needs to come to a near break-even point to be successful in my own eyes. If you're trying to achieve ROI in a space heater, I believe that you're not trying to solve the correct problem. Remember, you're a miner trying to make a profit mining.
the problem to solve, truly is to heat a home in a financially more efficient way. If there's a reduction of the home users' power bill because the miner recoups some of the cost of generating heat by generating coin, is that not the actual ROI?
Finally, you must also consider, this is but one method of repurposing older gear. There are many more that I'm currently aware of. We are not limited to single ideas on how to improve the network while improving people's lives. Nor are we limited by the short-sightedness of unrealistic expectations of instantaneous ROI that is so prevalent in the cryptomarketplace. Instant ROI simply isn't real in the long term, and is currently a function of novelty and adoption rate. The idea that you can buy miners today, and profit tomorrow is fading quickly. Please note the endless series of scams, scamcoins, and so on that point to frustration with the length of time that it takes to achieve ROI mining. In most businesses it takes 2-3yrs to start realizing a profit. Miners expect a profit in 60days. This is not sustainable.
As for "51% abuses" - in reality one need not have 51% of a network to attack it. In practice, the primary "attack" performed against most blockchains is one that even bitcoin is still susceptible to, and that is "selfish mining" - there are various ideas on how to solve that problem, and the Mazacoin Development Team is actively working on the issue. Selfish mining only needs 25% of the network to be effective, and we see this in bitcoin everyday.
It's my opinion that the majority of algorithms in use today have the same issues as sha256. Each has grown, CPU-only coins are GPU, with FPGAs on the way, and soon to follow will be asics for the most profitable algorithms. Certainly mazacoin will need to grow and adapt, but there is not a reason to change the sha256 algorithm to deter attackers, or selfish miners - these problems are present in each algorithm, and each PoW scheme devised at this time. Multi-algorithms simply increase the challenge to would be attackers and selfish miners, but don't solve the fundamental issues.
I certainly have considered all of this.
ill give you some basic examples to add some light to my previous statements.
say for example that you buy a cheap off the shelf miner for a few hundred dollars.
at current difficulty and prices you will likely earn less than 1$ worth of MZC a day for running it 24 hours a day.
your cost in electricity is likely to be a couple of dollars.
this means that currently, older generation miners have a negative ROI..
ie. the coins cost more to produce in electricity than they are currently worth.
this problem only gets worse over time so by the next cold season the very same mining hardware will be able to produce much less MZC (only a few cents worth)
so you can compare an asic unit which may cost a few hundred dollars to a convection heater which can cost less than $100 and it is easy to see that the convection heater is the more economically sound decision.
lets not forget that of all the energy sources (fire, solar thermal, electricity, gas) electricity is the LEAST efficient way to heat a home.
now as for 51% attacks, multi-pool raids etc.. I don't think you understand that it is much cheaper to hire enough hashing power to attack a sha256 coin that isn't bitcoin than it is to attack say scrypt or X11 coin. so yes you can claim that all small coins are susceptible to attack and but coins that have a flood of cheap ASICs on the market are much easier and cheaper to attack. thus Sha256 is much easier to attack than Scrypt and Scrypt is much easier to attack than X11 simply because the hardware required is much cheaper to hire or purchase. Not only that, but given the relative size of Bitcoin vs MZC it is by far much easer to redirect a mining pool with enough hash to crush small sha256 coin than it is to do so against any other algo. This is why there are no new Sha256 coins being released these days and it is also why most scrypt coins that were released recently are suffering badly.
these are just the simple facts of the market place as it stands today.. so please don't say that algorithm has nothing to do with it.. it only demonstrates that you do not understand how such attacks are carried out.
the one thing I would agree with you about is that switching algo is just kicking the can down the road. it is just pushing the problem away for a year or two at best but at least it gives you some breathing room to grow a coin before it becomes an easy target.
right now MZC is a very easy target... for me 51% attacks are nothing more than a way to frighten children who do not understand what can can't cant be done with a 51% attack.. but they are enough to do damage to a coins reputation and price such that it becomes harder to use the coins held in a trust for development work. so the threat of attacks of any kind should be taken seriously....
I think you are right though the focus should be more on establishing the trust, the legal framework and securing those premined coins. I was just pointing out that at some point in the not too distant future network security will become the big issue of the day.