I'm sure you know this but...
The current trend for gel or gel block type fuel has, I suspect, been driven by the military who were somewhat concerned that some of their preferred fuels (hexi for example) produce rather nasty fumes. I think it has basically been a health and safety thing.
Many of the gel type fuels are alcohol based, often some sort of bio-ethanol, and so should be fairly harmless. They are also expensive. There are some that aren't ethanol and they tend to be palm oil which makes them burn pretty dirty.
If you've ever eaten buffet type food, say a buffet breakfast in a hotel, you will notice little fires under the food to keep it warm and these tend to be fueled by, usefully, bio-ethanol. This is sold in huge catering sized tubs (usually about 4kg each) for something less than £20 and is bio-ethanol with a little bit of colouring and something to turn it into a gel mixed in. These tubs are sold as chafing gel and can provide you with the same stuff as the various "bushcraft" fuel blocks or packets for a tiny fraction of the cost.
Chafing gel is also available (for the catering market) in smaller tins with the idea being that you burn the fuel in the tin, under the food, and for some people this could make a very lightweight and efficient stove in itself, all you'd need as a simple mechanism to suspend the pot over the flame. I personally prefer to purchase the big tubs and for use in the field I decant a supply into a plastic 1/2l milk bottle, the gel is liquid enough to easily pour from the bottle into my Crusader stove for example.
So, if you are inclined to look at expensive ethanol type fuels it is worth considering that chaffing gel might be the very inexpensive answer to your needs, it's basically the same stuff without the packaging. A search on "chafing gel fuel" or "chafing dish fuel" will turn up no shortage of suppliers or dropping into your local catering supply store might also see you coming out with a tub.