Understanding Metavariants., If someone could lend a hand. Options

[Nimsul]

I've been skimming through the Runner's companion and am mostly pleased with it. I'm trying to wrap my head around Metavariants and their abilities.

Do the abilities Listed add or subtract from the prices of Metavarients or are they included in the package?

Do they follow the SURGE rules as are based off Base Meta Humans with Metagenetic qualities?

Examples:

Night Ones get Keen Eared, Nocturnal, Mild Allergy (Sunlight), Unusual Fur, and Lowlight Vision and cost 35 BP.

Minotaurs get Goring Horns, Metagenetic Improv (Body), Thermographic Vision, and +1 reach and cost 45 BP.

Do you then Add add/subtract the abilities from the cost?

Night Ones, Keen Eared: 5BP, Mild Allergy (Sunlight): -10BP, Unusual Fur: -5 BP, Nocturnal: -10BP, Lowlight Vision: 5BP
Total Cost: 35(+10)(-25) = 20 BP to play a Night One?

Minotaur, Goring Horns: 5BP, Metagentic Body: 20BP, Thermographic Vision: 5BP, +1reach: 5bp (as elongated Limbs?)
Total cost: 45(+35) = 80BP to play a Minotaur?

Or if you cross out the shared Racials with their Parent metahuman, (lowlight Vision, reach and Thermo Vision respectively).

Night One: 15 BP, Minotaur: 70 BP (Possibly 60 or so for losing Dermal Armor and gaining Body?)


I'm just trying to get a grasp around this. These 2 examples are on opposite sides of the spectrum where 1 gets a whole lot for their price, and one gets a ton of penalties for their price.

And if I did this wrong, and What you see is what you get including Price, why didn't they just use a SURGE system to just make all of the Metavariants? It looks like a good universal system.

Thanks in advanced all wise Dragons of Shadowrun. /bow