diff --git a/src/core/config/mod.rs b/src/core/config/mod.rs
index a58bcfe5..00623f44 100644
--- a/src/core/config/mod.rs
+++ b/src/core/config/mod.rs
@@ -2096,8 +2096,7 @@ fn default_servernameevent_data_cache_capacity() -> u32 {
 fn default_stateinfo_cache_capacity() -> u32 {
 	parallelism_scaled_u32(500).clamp(100, 12000) }
 
-fn default_roomid_spacehierarchy_cache_capacity() -> u32 {
-	parallelism_scaled_u32(500).clamp(100, 12000) }
+fn default_roomid_spacehierarchy_cache_capacity() -> u32 { parallelism_scaled_u32(1000) }
 
 fn default_dns_cache_entries() -> u32 { 327680 }
 
diff --git a/src/core/matrix/state_res/event_auth.rs b/src/core/matrix/state_res/event_auth.rs
index 0726b00a..759ab5cb 100644
--- a/src/core/matrix/state_res/event_auth.rs
+++ b/src/core/matrix/state_res/event_auth.rs
@@ -13,7 +13,6 @@ use ruma::{
 		power_levels::RoomPowerLevelsEventContent,
 		third_party_invite::RoomThirdPartyInviteEventContent,
 	},
-	EventId,
 	int,
 	serde::{Base64, Raw},
 };
@@ -22,6 +21,7 @@ use serde::{
 	de::{Error as _, IgnoredAny},
 };
 use serde_json::{from_str as from_json_str, value::RawValue as RawJsonValue};
+
 use super::{
 	Error, Event, Result, StateEventType, StateKey, TimelineEventType,
 	power_levels::{
@@ -217,9 +217,8 @@ where
 	}
 
 	/*
-	// TODO: In the past this code was commented as it caused problems with Synapse. This is no
-	// longer the case. This needs to be implemented.
-	// See also: https://github.com/ruma/ruma/pull/2064
+	// TODO: In the past this code caused problems federating with synapse, maybe this has been
+	// resolved already. Needs testing.
 	//
 	// 2. Reject if auth_events
 	// a. auth_events cannot have duplicate keys since it's a BTree
@@ -251,33 +250,11 @@ where
 
 	let room_create_event = match room_create_event {
 		| None => {
-			error!(
-				create_event = room_create_event.as_ref().map(Event::event_id).unwrap_or(<&EventId>::try_from("$unknown").unwrap()).as_str(),
-				power_levels = power_levels_event.as_ref().map(Event::event_id).unwrap_or(<&EventId>::try_from("$unknown").unwrap()).as_str(),
-				member_event = sender_member_event.as_ref().map(Event::event_id).unwrap_or(<&EventId>::try_from("$unknown").unwrap()).as_str(),
-				"no m.room.create event found for {} ({})!",
-				incoming_event.event_id().as_str(),
-				incoming_event.room_id().as_str()
-			);
+			warn!("no m.room.create event in auth chain");
 			return Ok(false);
 		},
 		| Some(e) => e,
 	};
-	// just re-check 1.2 to work around a bug
-	let Some(room_id_server_name) = incoming_event.room_id().server_name() else {
-		warn!("room ID has no servername");
-		return Ok(false);
-	};
-
-	if room_id_server_name != room_create_event.sender().server_name() {
-		warn!(
-			"servername of room ID origin ({}) does not match servername of m.room.create \
-			 sender ({})",
-			room_id_server_name,
-			room_create_event.sender().server_name()
-		);
-		return Ok(false);
-	}
 
 	// 3. If event does not have m.room.create in auth_events reject
 	if !incoming_event
diff --git a/src/core/matrix/state_res/mod.rs b/src/core/matrix/state_res/mod.rs
index a2052b92..651f6130 100644
--- a/src/core/matrix/state_res/mod.rs
+++ b/src/core/matrix/state_res/mod.rs
@@ -726,12 +726,8 @@ where
 	Fut: Future<Output = Option<E>> + Send,
 	E: Event + Send + Sync,
 {
-	let mut room_id = None;
 	while let Some(sort_ev) = event {
 		debug!(event_id = sort_ev.event_id().as_str(), "mainline");
-		if room_id.is_none() {
-			room_id = Some(sort_ev.room_id().to_owned());
-		}
 
 		let id = sort_ev.event_id();
 		if let Some(depth) = mainline_map.get(id) {
@@ -750,7 +746,7 @@ where
 			}
 		}
 	}
-	warn!("could not find a power event in the mainline map for {room_id:?}, defaulting to zero depth");
+	// Did not find a power level event so we default to zero
 	Ok(0)
 }
 
diff --git a/src/service/rooms/event_handler/handle_outlier_pdu.rs b/src/service/rooms/event_handler/handle_outlier_pdu.rs
index f9889d58..5339249d 100644
--- a/src/service/rooms/event_handler/handle_outlier_pdu.rs
+++ b/src/service/rooms/event_handler/handle_outlier_pdu.rs
@@ -119,7 +119,10 @@ pub(super) async fn handle_outlier_pdu<'a>(
 	}
 
 	// The original create event must be in the auth events
-	if !auth_events.contains_key(&(StateEventType::RoomCreate, String::new().into())) {
+	if !matches!(
+		auth_events.get(&(StateEventType::RoomCreate, String::new().into())),
+		Some(_) | None
+	) {
 		return Err!(Request(InvalidParam("Incoming event refers to wrong create event.")));
 	}
 
diff --git a/src/service/rooms/timeline/mod.rs b/src/service/rooms/timeline/mod.rs
index 74c7348d..e65ae2c7 100644
--- a/src/service/rooms/timeline/mod.rs
+++ b/src/service/rooms/timeline/mod.rs
@@ -698,20 +698,6 @@ impl Service {
 			.await
 			.saturating_add(uint!(1));
 
-		if state_key.is_none() {
-			if prev_events.is_empty() {
-				warn!("Timeline event had zero prev_events, something broke.");
-				return Err!(Request(Unknown("Timeline event had zero prev_events.")));
-			}
-			if depth.le(&uint!(2)) {
-				warn!(
-					"Had unsafe depth of {depth} in {room_id} when creating non-state event. \
-					 Bad!"
-				);
-				return Err!(Request(Unknown("Unsafe depth for non-state event.")));
-			}
-		};
-
 		let mut unsigned = unsigned.unwrap_or_default();
 
 		if let Some(state_key) = &state_key {