Hi Dana and welcome to TFF!
You've asked such a general question that it'll be hard getting answers out of members or the answers will necessarily be pretty general or personal. Stocking and knowing individual species characteristics are just pretty big topics for the hobbyists here... well anyway I'm thinking that's probably good background to say for you, going in to this.
That said, I'll throw my own little 2 cents of comment in: I've found small danios (zebras, leopards etc.) and rasboras (harliquins) and some cories to be pretty hardy for easing a tank through the first months after fishless cycling. Neons/cards, various other tetras, cichlids, panda corries, thousands of other fish, are ones where people usually give the tank more time to mature. The platies you mention, like swords, are very, very hardy too and good early on, but I always caution beginners to go into the thing of having livebearers with open eyes, as having a lot of babies puts one more new thing on you as a beginner that's another learning curve thing, and usually beginners have their hands full with water chemistry and tank startup learning.
The thing of "waiting even more months after the tank is cycled" often just "freaks people out!" They want to know "Why?" and we can't really give a good answer. I think its because out of necessity the water chemistry topics are greatly over-simplified and really there are a lot of "cycles" (there are "physical changes" going on that are different from the "biological cycles" that we spend so much time teaching and there's just more change going on during the first year of a natural body of water getting settled down than there is later.) So we as hobbyists are probably fairly ignorant of various things going on that we don't know or find too expensive or difficult to measure. We just know "little rules of thumb" that we reapeat to each other like "don't add neon tetras until the tank has aged 6 more months after the fishless cycle."... stuff like that.
Anyway, probably the other members will have more "hardy" suggestions for you. I expect the tiger barbs are hardy too ('course they cause other problems, with being so aggressive) but would be better if others confirm that. The guppies are sort of a different story in that they tend to be somewhat "in-bred" and potentially more susceptible to bacterial infections, perhaps, and so I guess some people wait a little longer on them but others think its ok if the tank has been well-cycled (passing its "qualifying week" and all that.)
~~waterdrop~~
