If you can get really good at one aspect of any craft, the rewards will follow.
Half of becoming successful is promotion and the other half is craft (businesses call it Marketing and Innovation). There are many other factors, such as your personality and the people you know, but those are much harder to change, so I won't discuss them in this post. Instead I will focus on craft.
Remember, anything you do will only make you better at doing it, and will make it easier to do in the future.
This is something that is extremely important to remember both in life and in your acting career. Because humans are psychologically wired to become better at tasks as they practice more often, no amount of practice will hurt you.
The question is: How much practice should you do on one technique before moving onto another?
Practice makes perfect, so after perfection comes, should you move onto something else? First, know that nothing can ever truly be perfected. Therefore, you should practice as often as possible at one skill that you enjoy the most. Of course you must be proficient in all areas of acting if you want to stay competitive, but if you can focus on one specific type of character, or one specific type of dance, and you become so good at it that you have branded yourself, you will likely become much more successful.
Remember that those actors who have become typecast typically find lots of jobs because their name starts floating around the industry. Casting directors want them in their film because of the name recognition and because they know they will be the best at that role. Then, once you’re getting called all the time and the money is flowing in, then you can feel comfortable trying those new roles.
Practice as often as you can, and master something specific. Keep other skills in case you need them, but if you get typecast into a specific role you will get your name known, and people will start searching you out for jobs because you’ll be recommended often. But until your name is known, actively search out the roles you want so that you build up the name recognition and the samples you have. After that, it’ll start building itself.
Just make sure that you focus on one aspect of a specific genre. That is how specific you want to get. Rather than being known as “just a comedian,” it’s better to be known as, “the comedian who always makes fun of ‘jobs at the office’” or something like that. Being known for something specific greatly increases your chances of being memorable.
Don’t be a “Jack-of-all-trades, and master-of-none”. It won't help you. Master one, and success will follow in all others.