I think there's a lot going on here. I'm taking from your message that you see yourself in a negative place, however I believe you need to reframe that thought. There's a few questions you need to ask yourself before speaking to your manager:
- Is consulting the right industry for how I want to work?
- Are my expectations of my work reasonable with the organization I'm working in?
- Are my observations of my DS colleagues based in fact or judgement?
- Who do I want to be in the work place?
Consulting, by its nature is a fast-paced all-hands-on-deck industry. Principals will rely heavily on can-do and will-do people and others will eventually get weeded out. Only the cream that rises to the top will be saved and this doesn't always mean the most talented individual, but the one that consistently delivers good quality work for the client.
Looking at the work you are being given, to me it appears a split between supervisory work (mentoring, integration of other Data Scientists code), trusted associate work (debugging, testing, client presentations) and other technical task you're capable of (cloud deployment and integration). My impression is that you are being relied on to do this stuff because you are trusted and capable, and you're not another DS who hides away in a corner plugging away at MatLab, Python, Apache, Excel, etc.....
The next thing to consider is your particular organization. Is the consultancy known as an "everyone chips in" or a strict "everyone sticks to their lane" type of place? If it's "everyone chips in", then it's the other DS's who aren't toeing the line and will see the consequences, not you. Even if you go out alone and hang a freelance shingle for yourself, you'll end up doing a lot of ancillary tasks for clients that have little or nothing to do with DS.
Another consideration is if the consultancy runs its own DS practice? If so you should be speaking to the practice lead about getting further DS tasks. Consultancies love an associate who can manage and organize a busy workload and won't disrupt something that is working well. To change this you need to be assertive and should maintain an open dialogue with the practice lead, understand how they see things and review your time recorded with them to show how much time is spent on other tasks. The person who is doing the assignments needs to know how you feel.
In terms of your DS colleagues, you shouldn't be too concerned with what they are doing and how they are doing it. Unless you're across their work you likely don't know the full story. While difficult, it's best to maintain an objective view that's not full of judgement in the workplace.
Finally, the biggest question you need to ask yourself is, who do I want to be in the workplace? This is something only you can answer. Do you want to progress into a management role, or do you want to be a pure data scientist? This is a very hard question to answer, especially at this stage of your career. If I'm reading things correctly, it would seem that the organization trusts and appreciates you so this is likely to be something that is put in front of you sooner rather than later. So it's up to you to understand whether the work you are doing is fulfilling for you; if it is then why try to change it, if it isn't then it's time to act before data science gets further out of reach.
As background, I'm a financial analyst who has yo-yoed my whole career between management and senior advisor roles. I enjoy being an analyst far too much and get bored of supervisory/management very quickly. I often fall into management roles because I have a lot of leadership competencies, but I'd rather be a thought leader in the areas I enjoy working in, than a people leader. My first management opportunities appeared about 4 or 5 years into my career and I thought I wanted it at the time. It was very good experience for me, but over time I naturally drifted back to the numbers. I've worked in consultancies, been a freelance consultant and been employed directly in very large organizations.