I am actually hoping they thought about a way the dropdownfields in flowcards are update too.
But yeah, else using autocomplete would do the trick yeah.
AFAIK you can’t change Flowcards for custom capabilities, but autocomplete would still work fine (only thing that you’ll miss is tag selection)
FYI - I use the Tuyal Local app by @Andi and that app allows me to set custom labels/entries for picker lists. The flowcards then also show those custom labels in their pull down menu. Maybe you could get inspiration from @Andi‘s implementation 
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But you can’t select a tag as the item, right? This means it uses autocomplete, which means the items that are shown are returned from the Homey app (backend). The advantage of this is that you can return any entry, and also first check with a server for example (the Spotify app uses it to get playlists, and the Olisto app uses it to get a list of Now buttons), however it does take a bit longer to load since the autocompletion has to be done on Homey first before it returns any items.
Not sure if I understand you correctly, but - as far as I can see - I can. Just for illustration. The respective device I control via the Tuya Local app is an airconditioner. It uses a picker list for the Mode and Fan Speed.
I can set the possible values in the device’s settings screen:
The flowcards for both setting the Mode and Fan Speed list these custom items in the menu that appears when clicking the respective parameter field in those cards.
Both the Mode and Fan Speed values are also available as tags:
This is an autocomplete field. Dropdown fields have a tag icon next to them so that you can insert a tag instead of pre-defining an option
Ah right, so you mean that you can select/insert a tag in the (in this case) Mode and Fan Speed flowcards, instead of only being able select/insert the actual values. In that case you are right: I need to select one of the available values and cannot inset a variable/tag holding that value.
Yes, that’s what I mean. Usually you use autocomplete fields if you need to fetch the items of the list from a server (f.e. my Olisto app uses this for the Now buttons and Triggs). Since each autocompletion has to be performed on the Homey app itself (and in most cases also fetched from the manufacturer’s server), it takes a bit longer to load the items
