Well, honing one's energy channeling skills is helpful for any magician. Personally, I recommend studying energy channeling, but that is just my opinion. Although a spirit guide or guardian angel could help you learn energy channeling and much more.
I've just not been a fan of spirits for most of my life. A few years of possession will do that to you... but I plan on reconnecting with a few trusted spirits soon.
Depending on your goals you should pick what feels best. If you don't feel a need to have an interactive guide right now than honing your energy channeling will allow you to achieve greater spells until you need a guide to aid you in your path.
I think the last two are the same... You don't necessarily have Angels protecting you, keep that in mind...
Those entities could teach you as well how to do energy channeling. Don't think any of them is too hard. For spirit communication, you can sit down meditate a little bit and call upon a spirit... Then, just open up yourself to receive what they have to say; thoughts will start popping up to your mind. If a thought is from your mind you can sense it; however to spirit communication, for me it works better to keep my self open instead of focusing on hearing an answer.
For energy channeling..I guess this is channeling energy from somewhere or someone to yourself or something? This is one of the Easiest things, I can do it cause I am a natural Witch though. It's done in any way you want, focusing eg on channeling Sun energy to you, or focusing on an object even through you and so on. Keep in mind that Sun is an entity and you will borrow his energy only if he wants to. :P
Im aware of the angel of the Sun, Uriel and the deities of the sun. Also I'd do personally believe there's a difference between a guardian angel and a guiding spirit I've communicated with my guardian angel before but it hasn't been on a consistant basis or with absolute clarity.
I'd say go with the guardian angel, if you really have one.
Just on base terminology, a guardian is there to protect their charge and protection takes a variety of forms (anywhere from basic guidance and suggestions to keep you from poor decisions, to actually keeping you from harm). If it's actually an angel, in the sort of traditional sense, they're a being of radiant good and just their presence in your life should make you feel better.
While I obviously can't prove that I had/have one, mine was pretty prevalent when I was younger and she saw me through most of my school years and into my first couple working years. I don't think I'd still be alive if not for her influence. Every now and then I still hear from her, like an old friend, but I've picked up being able to(pretty well) predict the world around me to avoid major problems and she seems to be busy lately.