Good question. Have you asked Lotus? Some S1’s were destined for hot climates where air con replaced the heater, so worked better. If yours is one of those then yes, keep it. If it is installed as per a uk S1 Exige then maybe ditch it for an Elise. Bear in mind that the a/c in the S1 Exige was always good for demisting, but not cooling the cabin effectively.
Personally I’d get rid of the carpets in case they promote the dreaded floor corrosion and bin the aircon as a power-sapping frippery. You can have all the fresh air you need by opening a window! Mind you I’m old and only bought mine for the lack of safety devices after a rogue airbag went off in my Clio V6 and damn near killed me…
That’s an ineteresting and very rare Lotus, congratulations. Any pictures to share?
Personally I would get rid of the aircon system. Simplifies the under bonnet installation and they don’t seem to work anyway.