Does it seem that your game starts to feel monotone? Keep in mind that you can change your Factorio server difficulty at any time for harder gameplay.
You will need to be an admin on the server to be able to change the difficulty, as you will have to use commands.
How to Change Your Server Difficulty
The difficulty in Factorio is affected by a handful of options that you can change, rather than having predefined difficulty levels. The changes are done via commands, which can be used in-game if you are an admin or from the game server panel console.
The following commands will help you change the options affecting difficulty on Factorio:
/c game.player.print(game.player.surface.peaceful_mode)
This will check if peaceful is enabled.
/c game.player.surface.peaceful_mode=false
This will enable or disable the peaceful mode.
/c game.forces["enemy"].kill_all_units()
This will kill all the biters in the enemy force.
/c game.map_settings.enemy_expansion.min_expansion_cooldown=ticks
This will set the minimum cooldown for enemy expansion events. Default: 14400
/c game.map_settings.enemy_expansion.max_expansion_cooldown=ticks
This will set the maximum cooldown for enemy expansion events. Default: 216000
/c game.forces["enemy"].evolution_factor=X
This will set the enemy’s evolution factor. The two values are 0 and 1.
/c game.map_settings.enemy_evolution.time_factor=0
This will disable time-based evolution.
/c game.map_settings.enemy_expansion.min_player_base_distance=-1
This will make biters ignore player structures and build next to walls.
/c game.map_settings.enemy_expansion.min_base_spacing=1
This will set the distance at which enemy bases can spawn next to each other. Default: 3
/c game.map_settings.enemy_expansion.max_expansion_distance=4
This will set the distance between an existing and new enemy base. Default: 7
/c game.difficulty_settings.recipe_difficulty=1
This will set the recipe’s difficulty. The two values are 0 (normal) and 1 (expensive).
/c game.difficulty_settings.technology_difficulty=1
This will set the technology’s difficulty. The two values are 0 (normal) and 1 (expensive).
/c game.difficulty_settings.technology_price_multiplier=4
This will set the price multiplier.