If you use tieght restrictions like 1MB ChipRam, the game wont be better than Dune2. This would be illusoric. It will be much worse because you have less time and less experience than the developers of Dune2.
For acceptable results, raise the specs at least to RTG, 64MB RAM, 50MHz+.
Note: Programming is totally different, if you target low-spec, mid-spec or high-spec. Probably your choise depends on what you want to learn.
