I just can't seem to visualize or feel the exact spacing and length ratio between each piece
渦巻さん、
Since you are not working with an in-person teacher, I think all you can do for now is just keep writing hiragana and not worry about spacing and proportion. Don't worry, they will eventually become second-nature. But continuing to trace on those tracing papers will help.
I'll have to do it again with this section...
Do not practice sections that you have already practiced. (Don't worry, you have plenty of practice-writing the already-covered hiragana in future practice sections.) You need to keep moving forward and practice more new hiragana.
Time for a new hiragana:
Words with し (SHI) (hiragana number 12)
1. し one way to say four
2. しお salt
4. しか deer
5. あし leg; foot
6. うし cow
7. こし waist; hips
8. こうし Confucius (Accent the first syllable.)
9. しあい game; contest (Accent the second syllable.)
10. しこく (one of the four main Japanese islands) Accent the second syllable.
11. おいしい delicious (Accent the first and third syllables.)
12. おおさか し Osaka City
13. おかしい strange; unusual. (Accent the third syllable.)
14. こけし armless wooden doll popular in Japan (See link below.)
15. あ、い、う、え、お The first five hiragana
16. か、き、く、け、こ The KA hiragana
17. えいこく England
18. おいしい さけ delicious sake
19. おく えき Oku Train Station
20. さかうえ Sakaue (family name)
21. あいこ Aiko (girl's name)
22. さかうえ あいこ Sakaue Aiko (full name)
23. あさくさ こうこう Asakusa High School (accent the second syllable in Asakusa)
24. おおさか こくさい くうこう Osaka International Airport
Here is the Wikipedia page on kokeshi.
en.wikipedia.org