This specific situation isn't even a problem. For the meteor storm precast, its easily countered by an instant cast land protector. If the HWs were a bit smarter and put quagmire as well, bragi + memorize also makes it quite easy. Going in the portal at the same time also makes tarots less lethal since they cant target specific classes and the number of targets are just overwhelming for the single target low proc chance of the good tarot debuffs to do anything. Also, traps can just be ganbanteined from a distance, or remove trap by a stalker/sniper, etc.
Not that anyone is doing this anymore but if you really want to prevent portal camping, its the ensemble skill "loki's veil" that you should look at since countermeasures against this is very limited and requires alot of players to push through.
About the guild limit, not that I'm totally against the idea because I personally played WoE servers that just has 20 main guild + 3 mbk guild and stuff. But you gotta consider that the situations in WoE guilds in tro are a bit different. WoE server guilds are organized through having a large pool of players. Hundreds of contacts, being chosen and contacted through skype/facebook/discord. They get assigned what class to play and will have their gears prepared instantly (if its an instant woe server) or easily (coz of the high rates in the server) by the organizers or friends. Here in TalonRo, its different obviously, the players who has the gears or the experience to play specific roles are limited. In the current situation of the guild I'm playing on for example, one of our DD Chems cant afford to get a Valk Armor atm, but we still go with it. There's also players who would like to only play roles that they like. And maybe its part of the social aspect of this server, but you can't absolutely abandon them, or at least through my perspective.
The current woe member guild limit in my opinion is good for the situation were in. You can put core classes while accommodating a few extras who are either new to WoE/undergeared/doesn't want to play standard classes etc. Also, having a bit more than 30+ makes it possible for members to switch roles in case some of the crucial class' internet died/power outage/ or cant come due to emergencies. This happens alot in WoE servers were the guild just cancels woe entirely because one or two classes are not online.