Here is a link to one of the listings:
http://www.ebay.com/sch/kg5collecto...0.m270.l1313Australia Decimal $1.50 High Value International Panoramas 2001 Used
To me, it looks like you have it pretty well covered. the idea is to put the information that people will search for in the listing title and you are doing that mostly.
You have the denomination or dollar amount, which is searchable, with or without the dollar sign.
You have the year of issue.
You have the series name.
Missing the actual stamp name, Port Douglas for this one.
If I was looking for one stamp or a stamp here and a stamp there I would start searching with a catalogue number.
This is hard for a seller to cover sometimes as there are so many catalogues. But if you do list a number then use the two letter abbreviation of which catalogue it is that you are using (Sc for Scott), then the number = Sc654 so a search can find it.
Typing it like this Sc654 and then searching for just 654 will find 654 and SC654 and #654 and also unfortunately SG654 etc.
If my search for a catalogue number didn't work I would use what I thought was part of the name of that stamp and then after than didn't work the series name.
Sometimes I would use the year but that usually returns too many stamps.
Having all the pertinent information is much more important than whether the stamps are all listed in order or not, which the first time through they will be (as you say) but after that they most likely will not.
One way around this is to put a statement in your listing stating you have other high value stamps from the same series listed at this time also.
You could go to the trouble of listing all stamps that you have from one series in order and then when those listings end go at it again and list all the stamps from that series again in order. A lot of work for not much return I am thinking.
Much better would be to have a clickable list within your listing of all the other stamps from that series so when a person clicked on the list (eye candy) they would be taken to an
ebay search that listed all those serie's stamps.
This would be accomplished by making sure you include the series name in each listing's title so it can be found by search.
One fellow (forget the name) on
ebay has his whole store arranged like this that you can search for this type of stamp or that type by just one click, and the great thing about this is, it keeps the buyer in your store or listings.