Okay! Well if you want to get really hardcore about it, you should check out smogon.com. They have articles about each pokemon and what their best movepools are, and articles about how to plan a balanced team. Do the terms “wall,” “sweeper,” and “tank” mean anything to you? They are categories of different “roles” each pokemon on your team can serve. There is an enormous base of really hardcore pokemon strategists out there, and they put all their ideas and findings on Smogon.
If you don’t want to be quite that hardcore, maybe your goal could be to arrange a team based on what types each pokemon is, always making sure one pokemon covers another’s weaknesses, and that you have a pokemon that will be effective against any type you might encounter.
For example, a potential weakness I perceive is that a rock type pokemon would be super effective against Taillow and Torchic, and rock types frequently have ground type moves, so it might be super effective against your Electrike as well, Zigzagoon would only get “not very effective” STAB hits, and Ralts has very poor physical defense, so even without a “super effective” hit, a rock type could potentially take him down too (although he would probably outrun it and might take it down first). Lombre would take a rock type down no problem, but if somebody else had already fainted your Lombre, you could be in trouble.
Gardevoir and Blaziken are both good picks that balance each other well. This is because Gardevoir has high special attack (and not very good physical attack) and should therefore specialize in special attacking, while Blaziken is the opposite. Plus Blaziken can kill off those dark types that would pose a big problem to Gardevoir.
Linoone’s stats are really…meh. He’s not particularly strong or fast or sturdy, so he doesn’t fit very well into any particular role. Swellow isn’t a great attacker, but is super fast. You could use him to “set up” annoying attacks like toxic or swagger.
Just some thoughts. Smogon has crazy good analysis on this kind of stuff if you feel like reading up!