This is working today in custom commands- hooray!

There seems to be a limitation. You may only issue a custom command "Once" and I believe it must be at the end. This is probably to avoid a Denial Of Service attack by calling a routine that calls back into your routine creating an infinite loop. That is really unfortunate because you can't program very effectively when you are "only allowed to call a function once... at the end".

Can I assume that this issue has been resolved to some degree by the Custom Command option in Alexa routines?

What I still want to see is an option to pass spoken options to a routine.
As far as I know, the only way to create a single routine to do...
Set volume to 1 on MySpeakerGroup
... is by using a custom command, e.g. set up routine MyVol

However, you need to create more routine to set volume 2 or 3,etc!

Surely, you want to be just be able to say...
Alexa, MyVol 1
... or any other volume level.

Hence, just 1 routine for many actions.

Is this currently achievable ??

this is critical otherwise skills are under utilised

100% this. I’ve been wanting this ability since I started using Alexa (this and logic gates in routines).

Would open up so many possibilities. Why can I tell Alexa to “play Archer using Netflix on the FireTV” and it works perfectly, but I can’t perform the same function, or even turn the FireTV on as part of a routine?

Definitely need to be able to process a list of commands. Even most CAD packages have a LISP processor to process a set of commands like a macro. I have a security system with an EnvisaLink module and it works pretty well. I can arm the system, disarm, and get some status information. But, in order to get the status of a door or window zone, you need to Ask Alexa if the front door is open. When you have 64 zones, it’s value becomes depreciated. If I could just create a named group/list and check all the sensors that I want in that group and call it by name, Alexa should be able to traverse the list and tell what door/windows are open or closed. The same could be done with other sensors and the panel itself to tell you if Fire, CO, Gas alarms are latched and what the Arming state of the panel is in, Armed Stay, Armed Away, Armed MAX, Disarmed, etc. it’s cool, but a little too tedious to asked the status of each one. It’s easier to go look at a panel, or to just arm it and have it tell you what’s open/faulted.

This would be great, especially if they allowed nesting so that a routines can execute each other, providing the are set to be voice commanded routines.

I have 6 philips hue lights in my bathroom. I created routines for normal color temperature, and special modes for makup application, and nightlight mode. Each of the 6 bulbs needed an individual step in the routine which was a real pain to set up and maintain. It would be great to add a steps such as "set the master bath lights to Daylight white" and "set the master bath lights to 100%" for the entire group rather than each individual bulb.

This is what I need as well. I want to be able to say "Alexa, fill the pond" and have a routine called "Fill the pond" that does "Perform 'Alexa, ask Netro to run zone 4 for 20 minutes'." I want to check my home weather station by having a routine "Check the weather" and it does "Perform 'Alexa, ask Ambient Weather for the outside conditions'." I don't want my wife to have to know about Netro or Ambient Weather.

Implementing this feature would provide a way to do many of the things people are asking for including the recently implemented feature allowing you to use skills in routines, which so far, is much less useful than it could be since all it appears to do is open the skill. Other examples of requests that could be sloved by this are this https://alexa.uservoice.com/forums/906892-alexa-skills-developer-voice-and-vote/suggestions/33151909-adding-a-new-custom-routine-should-enable-to-sto and this https://alexa.uservoice.com/forums/906892-alexa-skills-developer-voice-and-vote/suggestions/37122241-trigger-other-routines-in-a-routine and this https://alexa.uservoice.com/forums/906892-alexa-skills-developer-voice-and-vote/suggestions/33151909-adding-a-new-custom-routine-should-enable-to-sto and this https://alexa.uservoice.com/forums/906892-alexa-skills-developer-voice-and-vote/suggestions/38797276-allow-users-to-invoke-skill-intents-in-routine C'mon Amazon, here's you chance to kill multiple birds with one store and make the new "call skills for routines feature" actually useful in the process.

I love this idea too!! I want to convert a Alexa command to multiple Alexa commands. So for getting say multiple stock prices without having to specify each one, I want the voice command "Alexa, play stocks" to convert to:

1. "Alexa, get me the stock price of Amazon" (this would then follow its usual Alexa command processing)

2. "Alexa, get me the stock price of Microsoft"

...etc

Now routines seem to be the perfect way to do this as I can simply add multiple actions. But there is no action to trigger a new Alexa voice command processing. It seems like such a simple and obvious requirement to reuse Alexa's built in capabilities than having to use a skill here.