Your Raid Badge scores
I am curious to hear how many raids you have done and what your situation is. My case:
Champion badge: 51
Battle Legend badge: 14
Situation:
Living in a village. Only 0.5-1 hour per day available during raid hours in work city where people actively raid. Was out of country during Legendary Bird summer, missed out on those.
(I scale very low but actually don't care too much about most of the legendaries, but I really miss the number of Rare Candies and TMs)
Answers
You should have no problem doing group raids in a city. Just be at the raid when it starts and there's probably a group. That's how it's worked for me in several European capital cities.
I would not hold my breath for Niantic implementing a communication system. For all we know that might be months or a year away.
I've tried that several times in various parks where people are all over the place. There were 2 Legendaries right next to each other. Nobody came.
Also, used a lure module at a pokestop near them in an attempt to ask for help.
I've joined a Facebook group (on my PC though) and waited to see when people announce there's a legend raid. Turns out that whenever there is anyone to announce it, nobody can come on time. Mostly because we're always busy with something.
And also some people only want to raid with their fellow team members, they refuse to raid with other teams. Good luck finding someone who just wants to cooperate this way.
Try a park near a body of water. I have one I go close to the tram that people consistently raid to. I have played for a month and raided with valor and instinct once and all together another time. I went there twice to hunt some pokemon and twice we raided Groudon. I was told also that a park near the sea specifically is ideal for raids and rare pokemon and that people come there from even larger distances than me.
Herastrau is the biggest park with a huge lake near my area. I still can't find raiders, and when I do spot any, they're already walking back home and talking about what they caught with each other, so I don't butt in. 2 freaking Groudons there and nobody was around from the beginning of the hour until the end, same happened with the Moltreses that were right next to each other.
Another time there was a Groudon at the closest park nearby. I've seen players roam the area but they're all avoiding each other so I'm not going after them. Doesn't help that the average people judge you like you're the scum of the earth here if you play this game.
Champion:124
Legend:117
I live and work near a city which I have to drive around or through for my commute with an active raid scene (over 600 players), but where I live only about 8 people that live nearby are active raiders. So many of the raids I do are solo-T3 early morning on my way to work. I don't spend much on the game. Usually my coins from gyms goes to extra passes for solos while the daily usually goes to a legendary or T4 with hopes of TMs&rare candy.
They are really throwing out EX passes in my area like never before (9th and 16th). Raiding with a good group over the holidays, I was able to do some on weekdays from 10am to 1pm. At EX centric gyms I logged out of my account and played my wife's--they needed help on boosted Groudons. She received both EX passes, she has a 91% Mewtwo already. I logged out b/c these EX raids are almost always at terrible times on weekdays. Everyone from that group got at least one, several of them got two. Yeah, still not interested (Tuesday 12:30pm and 2pm)--already have 2 Mewtwos even though both 76%
Champion: 118
Battle Legend: 79
Never spent any real money, but almost never let a free pass go unused. I have bought maybe 30 premium raid passes with free gym coins, including 10 from the recent ultra box.
I usually have a limited window of time for coordinating with groups for legendaries, due to having to drive to another town, and raids usually ending around 7pm. However, I can often do a solo raid on short notice at various times throughout the day, if one shows up at a nearby gym in my own small town.
Estimate of current my raid activity:
T3 solos: 75%
Legendaries: 20%
Other: 5% (mostly T2 solos, and Absol duos with my daughter)
Champion: 42
Battle Legend: 121
(No EX)
I live in a big city with rampant spoofing, so it's usually not too hard to get into a Legendary raid in the right parts of town. My motivation has decreased because of the freezing weather recently (also am satisfied with my Groudon haul) but generally I try not to waste free passes if I can help it. I haven't put any money into the game in over a year and don't intend to anytime soon.
Champion badge: 33
Battle Legend badge: 71
Ex Raids: 2
Situation: LVL 35, only raiding during working days in a handful of gyms around my work (in Prague business area), with one of them being Ex Raid target gym. Typically 1-3 raids per day since September, depending on legendary availability or Tier 3 solo challenges. I returned to the game after 9 months not playing, hence the rather low amount of raids.
Champion badge: 55
Battle Legend badge: 116
EX Raids: 1
Live in a small town with about 12k residents, but also visits a nearby town with twice as many. Have also visited a big mall a few times where there's raids all the time.
At some points I also spent a few months at a different town with about 10k residents, but also fewer players. Actually, I was about 10km away, in a small house in the forest, but luckily I have a bike :)
At both places people have set up groups in Messenger so we can announce raids and see how many want to come. That has helped a lot.