One of the changes being reported is by comicbook.com (source) who are reporting that players are angry about the raid time changing from 1 hour to 45 minutes, the reason for this proposed anger is it doesn't provide enough time for players to gather a team to take on a raid boss effectively. I would argue that waiting around for an hour for players to turn up is just as frustrating but it's debatable and depends if you play as a large group of players are like myself tend to go around with 1-2 friends and see what you happen to run into.
The next and largest part of the Pokemon Go raid changes comes from Eurogamer (source) and Forbes (source) the first of the two reporting the changes on the raid bosses (and with some level of depth, acknowledgement and a little bewilderment at some of the changes) and Forbes pointing to the Silth road data mining exploits and listing the boss changes
Tier one changes don't worry myself too much as the only starer from generation 1 I have evolved is Venosaur - I use a method of only keeping Pokémon that are Simply Amazong so the strong, decent and below are cast aside. That said unless I was looking for a little XP I wouldnt touch the Metapod.
I don't understand Tier 2 at all, more so when you look over Tier 3 but perhaps it's a regional thing, all the above are part of my roster and Marowak has just come off it's second Halloween showing so you would have to be a very new player or someone that does not leave the house to have a low level of these perhaps Cloyster would be a handy one and the new Sableye is always welcome being a generation 3 Pokemon
Tier 3 I would argue is the best easily being out Tier 4 Scyther most players like have but a candy boost wouldn't hurt, Omastar took forever to walk off after finally catching a decent one and I don't have a Porygon despite a number of Upgrades in my items closet.
Tier 4 is perhaps the biggest one of concern as Poliwrath, Victreebell I feel most will have already - that said Niantic probably have real numbers to go off which will advise who has what so it may be a low evolution rate likewise with Golem - I would have preffered Politoad over Poliwrath (I do have a recently evolved Politoad) and Nidoking/queen are two I have as yet not evolved for no other reason other than they don't offer too much beyond a pokedex entry
So whats your opinions on the latest changes in Raids? Are you a big raid player or like myself a casual player that gives it a whirl every now and then?