As someone that played both rulesets - countless ESEA seasons, half a year in AsiaFortress / a couple LANs - I feel the EU / AU / global ruleset provides more overall.
Yes, halftime is cool to reset things / talk over but that can be "replaced" with a tactical pause option. Give each team one per match (with a max of like three minutes or something). I also think it rewards the teams that can adjust on the fly instead of needing to talk about it but whatever. Halftime drags out lengths of the standard match, too. LAN is another story. For time / logistical reasons we already use the EU ruleset. I know in NA we don't have (huge) yearly LANs (rip Rewind) but the equivalent is basically playoffs where things really matter. There would be no fears of a potential <insert large number> hour Grand Final which are headaches for players and casters alike.
Also something tiny worth noting is that halftime in NA ruleset involves switching colors, something that changes nothing because all our maps are symmetrical...except Viaduct... Shoutouts to old Granary when red Medic had to killbind during each rollout because of shitty spawns.
People talk about the potential for slower games and parking the bus, but that shit can and does happen in NA already. Some teams already scrim as if it's LAN GRAND FINALS and don't do things for eons anyway. Rounds mean more when there's a win difference of five / 30 minutes. A 4-3 lead in NA is way different than a 4-3 lead in EU. The whole round reset timer issue makes more of an impact when there are only 30 minutes total but how much does that actually change? It would be amazing if there was a way to run the numbers and see how many low scoring matches happen in both ESEA and ETF2L across the divs - even for the small sample size of a season - to compare. As far as I know there's no data on that...for obvious reasons (way too much work).
Some have brought up 20 minute halves with halftime before, which would be an interesting take. Perhaps an exhibition cup / tourney of some kind could be held to test it out?
Sorry for bad thoughts / English / formatting, yadda yadda been up since 5:30AM.