The success or failure of this tangy drink is partly reliant on the quality of marmalade used. For ease of use, choose "fine cut" or even "no peel"/"shredless"...
I too am not keen on the ice chips so I strained. It will depend on how fine a strainer you use obviously, but the strainer I used removed the ice chips well enough but surprisingly allowed some fine marmalade particles through which added some nice texture. (Our nanny from Scotland loved Mackay's Dundee Orange which is what I used!)