Raid is amazing. Using a local facebook group I was able to get in on a level 4 Raid with 10 other people. Had a chance to catch a 1900 CP wonder Snolax but it got away.
Not sure if like the new coin system as some of my Pokemons are not returning.
Agree on both counts. First, the bad... While in theory I can see where they were going with on the new coin/gym setup, there are 2 issues: 1) Obviously they cut the coin payout in half (from 100 per day to 50) so that sucks. 2) But the biggest problem is that you no longer have any control over getting your own coins.
Yeah, you need to wait until someone beats a Pokémon out of a gym, and it needs to happen once a day, but only after that Pokémon has been in for 8 1/3 hours. So what this has led to is me and my son trying to get as many Pokémon into as many gyms as possible. It caps at 20 and we haven't hit that yet but we've been in 14. Our strategy now is to go out around 11:30 - 12 midnight and take over any easy ones and put in low-level crap. Then we hope they can stick in there until 8-9am and if it gets beat then, we are good for the day. It has been working so far but it is considerably more work than the old system where we would be in some gyms for weeks and only had to retake stuff every few days at the most. it is almost like you are encouraged to set up a deal with someone from the other team and try to swap gyms every day. If you could get that down to one particular gym you wouldn't feel the need to take over every one you can in the hopes that someone beats one of them, but not too many of them at once.
Probably the simplest fix they could make here is to have the coin cap be weekly and not daily. Make it 350/week instead of 50/day. Problem pretty much solved, since you wouldn't have to worry about daily gym turnover - just take a bunch at the beginning of the week and let them erode as the week goes along.
The good... Raids are definitely fun, and are bringing out a lot of people I don't normally see in gyms. We have a Pokémon Go Facebook page for our small town and it was never really active before. There was the occasional "Snorlax spotted" post but by the time you see that it is usually too late to drive wherever that is. With the 2 hour countdowns on Raids, though, it is a completely different story. Still, this is a small enough town that we struggle to get people to beat the Tier 4's. Me and my son rushed downtown to beat a Tyranitar with 10 minutes left because a handful of people couldn't beat it. You need 5 people minimum for those it seems.
Anyway, it does seem that most of the Tier 4's are Tyranitar which is excellent since we never get Larvitars here. Both of my kids got their first Tyranitar that way. We've participated in 5 Tyranitar raids, 1 Lapras, missed a Snorlax one, and passed up a couple of Venusaur ones. We haven't even see the others (Blastoise, Charizard, and Rhydon) and I'm fine with that. The only other one we are even looking for is Tier 3 Machamp because my son doesn't have a good one yet and it is a great counter for the better Raid bosses (Tyranitar, Snorlax, and Blissey if/when they add it).
Of the 5 Tyranitars, I could only catch 3 of them (those bastards are slippery) and I got like the worst possible IVs: 76%, 80%, 84%.

. Really!? My son got a 98% one though. And my Lapras was a 96% which beats all 2 or 3 of the ones I've hatched by a large margin.
One small issue with raids and the one free pass per day thing is that Tier 1 and Tier 2 (and most Tier 3) raids are utterly useless. I don't think people do many of those. A potential fix here is to sell a 3-use pass for, say, 150 (like an incubator). Or maybe an all-day pass for 500 or something. Then people would be more inclined to do lower level ones.