Rather than using percents, I think that it should be listed as a multiplier (x4 instead of 400%). My suggestion for the display would be one column for weaknesses, and one column for resists (including immunities). List the weaknesses/resists in order of magnitude, eg immunities first, then x4 resists/weaknesses, then x2 weaknesses/resists. Whatever you do, don't list types that hit neutral, it's only clutter.
Weaknesses and resistances due to abilities should be listed also, but with the ability's name listed in parantheses afterward. This lets the player know about any special properties the immunity might have, like motor drive's speed boost. Additionally, this resolves some issues with pokemon whose weaknesses/resistances can change based on their ability choice (bronzong for example (also with bronzing, make sure it's x2 ground weakness has "heatproof" in parentheses afterward)). Unless you can think of some cleaner representation, possibly involving tabs, this seems like the best way to handle abilities.
Solid rock should probably not be accounted for as that would just make a mess. On a side note, I suppose parasect gets it's own x8 weakness category.
