The stutter that arrives at peak population is usually not server tick — it is client-side streaming pressure. Every custom vehicle, ped and map prop occupies a slot in a fixed pool, and once those pools thrash, players get the hitching that gets blamed on "lag".
Start by measuring. Open the client resource monitor and watch the streaming memory line during a busy hour, not an empty one. If it climbs toward the ceiling and stays, adding a faster server will change nothing.
The two biggest wins are almost always LODs and texture budgets. A map pack shipped without LODs renders full-detail geometry across the whole draw distance. A 4K texture on a road sign no one stands next to is pure waste. Downsample aggressively; players notice frame times, not texel density.
Cull your vehicle list. Most servers stream two hundred add-on cars and see fifteen of them driven. Every one of them costs pool space whether or not it spawns.
Finally, stagger your ensures. Resources that all stream on boot spike memory before the garbage collector settles. Load core first, maps second, cosmetics last.