Add more info about top N and optin

docs/docs/features/partial-set-security.md

@@ -10,7 +10,11 @@ Partial Set Security (PSS) allows consumer chains to leverage only a subset of v
 
     * Opt-In: If the top_N parameter is set to zero, no validator is mandated to secure the consumer chain. Instead, any validator from the provider chain can opt in using a dedicated transaction.
 
+An advantage of a Top N chain is that the consumer chain is guaranteed to receive at least a certain fraction of the market cap of the provider chain in security. In turn, this chain needs to be approved by governance, since validators will be forced to run the chain. Thus, Top N chains should typically expect to need to provide a strong case for why they should be added to the provider chain, and they should make sure they offer enough rewards to incentivize validators and delegators to vote for their proposal.
+
+Opt-In chains, on the other hand, are more flexible. While for technical reasons, they are also currently added via governance proposals, since validators are never forced to validate these chains and simply opt in if they want to, they should typically expect to get their proposals approved much more easily compared to Top N chains, since validators that do not want to validate the chain can simply choose not to opt in.
+However, opt in chains do not get a fixed amount of security as a relation of the market cap of the provider as top N chains do, so opt in chains might want to keep an eye on how many validators have opted in to validate their chain and adjust their reward emissions accordingly to incentivize validators.
+
 :::tip
 Partial Set Security is handled only by the provider chain - the consumer chains are simply sent validator sets, and they are not aware that this represents only a subset of the provider chains validator set.
 :::
-