But it just kinda sucks that one must pay for for slots with no alternative.

While I know the logical response is: 'just buy platinum if you like the game and play it alot' Which makes sense since you are playing a free to play game and should show support for the dev.

I vaguely remember back when open beta was first released that it was stated that slots being platinum exclusive was only for the beta period and a free method would be added at a later date.