Well I kind of imagined the field starting with plenty of veggies and letting them gain a descent amount of energy in order to reproduce, but not allowing any reprop. The main reason I think the field should be filled with veggies at startup is to minimize the effect of chance, if there's 10 veggies in a size 12 field then if someone starts next to a veggy he'll have a great advantage...
Not saying I'm fixed on the idea or anything, but I thought it sounded interesting. This would mean you either need to be strong enough to live off your oponent or you need to hamster food instead of just killing the alge you find. It would definately encourage antbot strategies, and with no viruses or raping you wouldn't be able to just take over the alge like in F1. So if you would have to make your way into enemy teritoy and kill their veggies to weaken them, like bombing fuel siloes during wartime.
But then again maybe this strategy would be the only way forward which could leave out other interesting MB's... but it seems to me that if movement is expensive and food isn't abundant and the field size is large, then hamstring food will always give a great advantage versus oganisms who just kill the alge.
Gotta admit I haven't thought it all the way through, just venting thoughts...
Not sure if shell costs are setled, but as I understand it -1 shots destroy more shell than -6 shots, but -1 shots also trigger poison if there's more poison than shell.
Now I don't know how much shell is destroyed by a -1 compared to a -6 shots. But for the sake of argument lets assume that a -1 shot destroys twice as much shell as a -6 shot, and lets asume that a regular unboosted -6 shot from a bot of size 1000 destroys 10 shell at the cost of 2 nrg. (I'm sure all these numbers are completely wrong, but this is just an example).
Now if the -6 shot destroys 10 shell the -1 shot would destroy 20... then I would set the cost of 15 shell to somewhere around 2 nrg. So the costs of 1 shell would be around 2/15.
This way if you're shooting -1 shots at an oponent that replenishes shell he will spend more energy on making shell than the oponent spends on destroying it. But if the oponent is using -6 shots he will spend more energy on removing the shell than the target spends on making it, however he won't risk getting affected by poison.
Now the problem is balancing poison with all of this... I would probably set it somewhere between the cost of shell and half the cost of shell. So you can use poison to force people to use -6 shots, but it will also cost you more. If the oponent chooses to use -6 shots because of the poison, then you won't need to replenish it and your shell will be worth the energy....
Not sure if this is the way to go, but it's what I had in mind...
And rememeber all the numbers used are make belief, it's only an example.
Also this isn't the specific way to balance it, but a sugestion for the reasoning behind the selected costs...