In that case you are not looking that hard... when you say "but I haven't seen solid grounds to only regard the little horn as a person..." and don't give any explanation or reason for the little horn to be other than a person.
In Dan 2:38 Daniel says to Nebuchadnezzar “you are the head of gold”, thus indicating the head of the statue represents him as the
king of Babylon. But in Dan 2:39-40 Daniel says that the chest & arms, the waist & thighs, and the legs represent
kingdoms that will come after the Babylonian kingdom.
So the body parts of the statue can represent both a king or a kingdom.
The meaning of “king” can be any kind of a ruler or authority while the meaning of a “kingdom” can be any kind of realm or region of authority.
In Dan 2:41 it is stated that the feet of the statue represent a
kingdom, but in Dan 2:44 the same feet of the statue are referred to as “in the days of those
kings”. So again this body part of the statue can represent both a king or a kingdom.
In Dan 7:17 the four beasts are told to be representing
kings, but in Dan 7:23-24 the same are told to be representing
kingdoms. So here the beasts also can represent both kings or kingdoms.
And finally, in Dan 7:24 the 10 horns that arose out of the 4th beast are told to be representing
kings,
the little horn is also stated to be representing a
king (wə·’ā·ḥo·rān “another” referring to the 10 kings).
In Dan 8:21 both the goat and the initial large horn that arose out of it are told to be representing a
king, yet the 4 horns that arose out of this initial large horn are told to be
kingdoms and that these 4 horns arose out of a “nation” (mig·gō·w) which is equivalent to a
kingdom, thus now stating that the goat and the initial large horn (also) represent a
kingdom. In Dan 8:23 it is again stated that the 4 horns represent a
kingdom (“their reign”) while the little horn is again stated to be representing a
king.
So the texts show that the body parts of the statue in Dan 2, the 4 beasts in Dan 7, and the horns in Dan 7 and Dan 8 can represent both
kings or
kingdoms interchangeably. This is in line with the concept in ancient times that a
king was the embodiment of the entire
kingdom.
Regarding the little horn the texts only indicate this to represent a
king, but because of the established interchangeability the text allows to also consider this little horn to represent a
kingdom or an empire.