Quote 1
"I keep [my diary] in this." As he spoke he laid his hand on the phonograph. I felt quite excited over it, and blurted out:—
"Why, this beats even shorthand! May I hear it say something?" (17.16-17)
Mina is as excited to see a real phonograph as we are to see the latest smartphone.
Quote 2
I feel very solemn, but very, very happy. Jonathan woke a little after the hour, and all was ready, and he sat up in bed, propped up with pillows. He answered his "I will" firmly and strongly. I could hardly speak; my heart was so full that even those words seemed to choke me. (9.4)
Mina hardly sounds like a glowing, blushing, happy bride. She says she's happy, but she almost seems to insist on it too much. Even the words "I will" seemed to "choke" her. Isn't she happy to be married to Jonathan?
Quote 3
I must stop, for Jonathan is waking—I must attend to my husband! (9.6)
Here's a taste of Mina's ideal of marriage—"attend[ing] to [her] husband." She's such a tender, maternal person that she nurtures everyone.