Mass Effect Andromeda – How to Quickly Regain Health During Combat

Based on my own testing, it looks like you get 1% for each 6 points invested in the tree. As Mad Scientist pointed out, the value displayed is the total.

Since it's also additive with other boosters, you won't generally get 5% more than your current value. For example, if you have +20% already from other sources, and then get a +5% from this, your original value of 300 is displayed as 360 from the other bonus. When you add this skill, it will go to 375. Since 5% of 300 is 15, you get that, rather than 5% of 360.

To specifically answer your question, I do not think they deliberately made it confusing.

According to this source (which seems consistent with other sources such as PC Gamer and IGN), this is the list of characters with whom you can romance.

Edit: Added some known commitment requirements for certain NPCs.

• Cora (Scott Ryder) - Commitment required.
• Liam (Sara Ryder) - No commitment.
• Peebee (Scott or Sara Ryder) - Commitment optional.
• Jaal (Sara Ryder) - Commitment required.
• Vetra (Scott or Sara Ryder) - Commitment required.
• Gil (Scott Ryder)
• Suvi (Sara Ryder)
• Reyes Vidal (Scott or Sara Ryder)
• Keri T'Vessa (Scott or Sara Ryder) - No commitment.
• Avela Kjar (Scott Ryder)

Notable:

• You can flirt with Lexi T'Perro but they shut down either Ryder.
• Some crew members have flirtatious interactions with other crew members.

Tips from the IGN guide:

"The way to romance characters is rather standard: flirt when you see the heart icon, and if the character is interested, they'll convey that to your chosen Ryder. Most will update their conversations after you complete a major mission or character specific mission that'll allow you to further your romance.

Flirting with every character at the beginning doesn't hurt your chances with the others later on."

Also noted about the romance system by the producer:

"Ryder's personality is slowly set by those tones, with new conversation options and character interactions unlocking when he or she reaches different thresholds within those personality types."