Most apps support both: opening the item from continue watching or playing it right away.
- On Plex Web that’ll usually depend on where you click… when hovering over the poster, a play icon will show on top of that poster. Clicking that will play the item, clicking anywhere else on this poster/label will open that items details/pre-play page.
- Similarly most of the big screen apps allow you to either click the item (=open its details/pre-play page) or click e.g. „play“ on your remote to immediately start playback.
- On a mobile client, clicking an item will bring up the details of an item… you can however also choose to directly play it from the long-press context menu
I suppose the first part of your request is actually implemented/available.
There’s already an existing feature suggestion for the second part of your request. I suggest you vote/comment in that thread to avoid distracting/dispersing votes (and help avoiding duplicates)