1) How do you think we should proceed with writing an article(s/?) about Remastered edition (as in: the game itself). We have few options:
We don't introduce any new articles. We'll do it like it's done on a Wikipedia - adding a description of Remastered edition into the existing articles. So wikipedia:Homeworld is an article about both: HW and HW Remastered.
Alternative would be to create an article "Homeworld Remastered" describing a re-release as a whole (cause after all, it was released as a whole pack, even though it's 4 games inside)
Or we could go for the most detailed scenario and write up separate articles for each remastered game (and if so - how do you think we should proceed with describing anything that's shared between them?)
2) There's a separate matter of describing things like ships and weapons from the remastered edition. If you have an idea - go for it.
My suggestion would be as follows:
An existing articles would receive section Changes in Remastered edition describing just that - what changed in the remastered edition - while infoboxes would have two tabs: Remastered and Classic as it is for example in SoulCalibur wiki, only not just an image would change from tab to tab, but also every statistic that's displayed in the infobox.