Having done most of my flying to date on OW/Star I now have some upcoming J UK-US flights booked on Delta.

I am looking for a ST programme that offers:

1) Miles don't expire - topping up miles through other activity (or using credit card to prevent miles expiring, if available in UK) is fine.
2) Status match from OW Sapphire (BA) or Star Silver (BD) - would OW Sapphire.
3) A decent earn-to-burn ratio when booking flights - one-ways and/or cash+miles would be useful.
4) Some opportunity to earn miles on discounted fares.
5) Reasonable availability when booking awards, ideally on other ST airlines.

Thanks for your suggestions.