Showing Correct Retail Price For Other Option? Improvement Of Cs-Cart Sorely Needed!

The title says it all I believe.

Ever since we started using CS-cart it has been a source of discontent for me that we can NOT show the correct discount relative to the suggested retail price for the OTHER option.

Most of our products for which we offer options, do NOT differ in colour but in size or if they differ in form have different retail prices as well!

While more expensive in absolute sense, a larger-sized product is much more economical in price when you do the math.

Ever since we started with CS-cart I have had the problem of choosing which of the 2 to show.

Showing the larger size as a lead product and deduct the smaller sized product from it as an option, results in
1 a seemingly much larger discount-% relative to the 'new' retail price (which isn't the correct SRP!)

2 people freaking out who want the smaller size as they think the price is for the smaller product

We now switched to the other side of the coin and show the LOWER priced product as the 'default' and ADD the price for the more economical size., this however results in

1 a seemingly much SMALLER discount % relative to the imaginary SRP (again, this is not the correct SRP)
2 people freaking out who want the larger size as they think the discount is way too small and we are being nasty!

I thought to remove the SRP/retail price and actually went ahead for some products, but then it seems we don 't offer a discount at all and we are penny-pinchers too (which is far from the truth)

I'm almost wanting to separate them again but am warned not to do this as it would be negative for SEO when you have 99% identical products that only differ in size and price.

Please advice! To me this has always seemed to be a huge bug .
TIA, Yvana