I guess reading based upon your favorite character and just align their stories on the upcoming interactions from the other characters is possibly the best choice to do.
I'm actually more of a Gambit fan, but I'm just quite not sure if I could entirely get to know the different races and entities in the MCU unvierse if I start from him. Because from what I understood after reading a few slips from these comics, it's always the popular characters that actually gets the reader to see more of the story behind these huge events. Such as Thor, Stark, Spiderman and popular characters from the X-men such as Wolverine and Magneto and Mr. Fantastic.
Gambit is a great character (one of my favourite X-peeps along with Storm, Wolverine, Nightcrawler and Beast) and is one of the few X-Men to have their own solo titles but he hasn't had one since 2013 so a couple of years before the major plot event I mentioned before.
One other thing to keep in mind is that each character represents a different kind of story and story telling method.
For example: Spider-Man is always written in the most down to earth fashion possible because the character at his roots only wants to help people and as much as he fights some seriouse big bads, his day to day world is stopping muggings/the occasional costumed criminal and dealing with the ramifications of his personal and hero life.
The Hulk is a series based on deep personal pain and grief, it's a story about a man who was heavily abused by his father as a child and who's mind split into several different personalities, all of which were dormant before Banner got into the accident that turned him into the Hulk. The most well known version of Hulk is Green Hulk (yes the colours matter but you'll find out about that sort of stuff if you read more of it), which is the physical emobodiment of his childhood and his childhood pain. Green Hulk AKA The Incredible Hulk is basically child Banner who wishes for nothing more than to be left alone because any and all pain terrifies him which is why he's desperate for the strength to be able to stop anyone from causing him that pain so he can be left in peace, combine that with the radiation accident and you have a dude with a split personality that has infinite strength dependent on his infinite rage and immortality (the latter used to be theory but is now confirmed and the title of his latest series so not really spoiers).
Thor is a story about a god who finds his humanity, learns that love transcends all things and that being a hero is more than just being a superpowerful deity that people "should" bow to. Also, the hammer never made him who he was he did etc. etc.
Dr Strange is all about the cost of arrogance and the price you have to pay for power, whether or not you use that power for good or evil, there's always a price and the ramifications of said price can be huge#
Spider-Man (Miles Morales) isn't a retelling of the old teenage spider-man days but a different coming of age story to do with a mixed raced kid who grows up with feet in multiple cultures and how this has effected how he grows and sees himself, in fact it's only recently that he's come int to his own, so to speak, as a character and purposefully put aside the mask and his own preconceptions so he can figure out who he really is as a person and a hero.
In terms of the different races and stuff, don't worry about it. The one great thing about comics that is never really spoken about is how good they are at referencing themselves. Whenever you see a character or species or something that isn't normally in the title you're reading but has been in something else, you'll see a little box in the art panel that has a reminder to readers as to which issues and story arc they were part of. This will give you a chance to either read those comics or do a quick google on them so you can get a rough idea of what's going on.
I also suggest using comicvine instead of wikipedia as they have more comprehensive info on all of them as comics are their main focus. whenever I have to search for a title or hero/vilain I go there, especially when it's not a mainstream or movie character.
