I'm not sure if adding more toplists would be beneficial, but I do agree with the general idea that there needs to be more of an incentive to voting. I personally wouldn't mind seeing the shop itself revamped. Even now, the most expensive items in there (by vote points) are worth less than 50M. The only reason people vote is to sell the vote books or take advantage of the double EXP they give when used. Speaking of which, if a player is claiming their vote books from the chest and they exceed the claim of 3 toplists, they should still get the according vote books. I.e. If you finally get in-game after a few days but have been voting consistently in that time, you shouldn't get only 3 vote books for voting on like 9 toplists.
My recommendation would be to add the following rewards (points TBD):
Champion's cape (cool looking cape that is useless in the achievement shop, no one will ever buy it)
Dragon platebody (useless in the achievement shop, no one will ever buy it)
Heart crystal (can stay in the achievement shop as well - it's an item that only HCIs/UIMs buy and since they can't sell vote books, it would be a perfect incentive for them to consistently vote)
Royal seed pod (this is a great universal item that works perfectly as a vote reward)
Gold leaf (a useful drop from a pretty unknown NPC by most - would work well as a vote reward)
Ward upgrade kit (very little of this circulating in-game from what I've seen, but would work well as a vote reward when compared to the ratio of odium/malediction wards in-game)
Occult/torture/anguish/fury ornament kits (not sure why these are in the ;;store at all - I would never make the recommendation to anyone to spend roughly $10 USD in credits on an ornament kit)
Gnome scarf (nobody is dropping 30M on this at Thessalia's shop..)
*Katana (read below for an explanation on this)
I have yet to see the standard coloured partyhats/h'ween masks/santa hat pass 100M in market value. Imo, these are items that should be much more desirable. Most people in the RSPS community would expect them to be, which to me is a pretty important stipulation to newcomers. My recommendation would be to remove them from the game entirely for 1 - 2 month(s) and then add them to the ;;store for a high price; the 1 - 2 month interim period will allow the price to flesh out and hopefully increase. In lieu of these rares, I would add:
Black santa hat
Black h'ween mask
This would definitely drive players to vote more or to purchase more vote books. In any event, it would ultimately lead to more voting. I understand that adding those items might be controversial, but earnestly speaking, the vote reward shop right now very unadorned and often ignored entirely.
Of course, each of these items should be set at a minimum of 75,000 points, imo.
As for the *katana, I added that as my idea for an alternating reward that would be changed on a monthly basis. As of now, I have yet to see a katana in-game. I am aware it is a rare clue reward, but it is by all means a cosmetic. Also, it is not considered a traditional rare clue reward like third-age and ranger boots. Just touching up on the alternating reward idea, I think it would be great if one item in the vote shop was added each month for a high amount of points, and then replaced by another rare item for the next month. The exclusivity and high point value would prevent a flood of said item into the economy and because of that, the alternating reward doesn't have to be restricted to a cosmetic. I only suggested a katana because it's the first thing that came to my mind as a desirable vote reward that would pair well with this idea.