Yep, poison should be reworked and most likely will be another thing changed by wipe.
On Wasteland2155 project I reworked it to 4-stage system, with thresholds: 1, 25, 75 and 125 poison levels. So, something similar to radiation. With every higher stage it caused more poison damage over time - higher poison level - more frequent damage. High poisoning level was quite deadly and made you think about getting an antidote (now on Reloaded and before on 2238 you could simply ignore poison, as it never posed a threat). It also lowered Strength and Agility (max. penalty -3 for both).