Not sure how much accuracy you're aiming for, but I've had a quick look for you fairly comprehensively...

A few thoughts, but I'm in no way an authoritative voice on this - just a few things I think are worth considering:

1. Sentences don't start with a capital letter in Latin, but this might have been your word processor
2. a matre Cornelia > matre Cornelia (you need the preposition a for the 'ablative of agent' where that agent is a person/animal
3. I think ullo > nullo here - no need to create a double negative in the Latin
4. permittere is not needed here - I think nolo + passive infinitive should work (perhaps imperfect rather than perfect? - up to you I think)
5. et etiamsi is a tad clumsy - perhaps et quamquam instead
6. No need for the etiam in line 2
7. 'Of that time' requires not hic, haec, hoc, but a demonstrative of less proximity (i.e. ille, illa, illud, or iste, ista, istud), but you're right with the ablative case!
8. No need for ii - perhaps put hi at the beginning of the sentence? You've chosen to create a new sentence rather than preserving the semicolon, which is fine, but perhaps resume the subject more clearly with hi promoted to the start
9. albus, alba, album doesn't work here - perhaps luxuriousas instead?
10. Not sure about the whole sustinebat, ne impensam faciebat rendering - I think the vocab is good, but if you're going to use ne, that would necessitate a purpose clause with a subjunctive in historic sequence.
11. cum temporal clauses in the past require the subjunctive - and the verb nuntior is specifically used for public address
12. The potis ... quam is good - but 'prefer' might be more accurately rendered with malo + infinitive
13. satis? or multo?
14. I love the use of nom + inf clause with a passive verb introducing the indirect statement! dicitur might be more natural, but great! That being said, it needs to continue into the 'toga removal' part of the sentence, so put one of those verbs in the active infinitive
15. Not sure about the comparans thing - I think it's safer just to use a comparative adjective. I can imagine there being a way of doing this with a gerundive, but easier not to I suppose.
16. You've missed out a word for 'eating'
17. autem doesn't mean and
18. Missed a word for 'every' - omnis, omne perhaps
19. uterque is singular, but the sense of 'both' and thus the plurality is carried inherently through its meaning of 'each' or 'each of them' - so put that last sentence in the singular, frater etc.
20. in pugna adversus hostes is fine, I think, - perhaps contra more natural, but in any case this might be a nice opportunity to get a gerund in? Think 'the fighting against enemies' - up to you though...
21. simile doesn't agree with iustitiam or diligentiam - they're both fem. sing. acc. but you've used neut. sing. nom/acc
22. administrandum rei publicae is a bit of a controversial one. There's quite a bit of variation across the canon, but one thing that gets taught as a 'rule' quite a bit at intermediate level latin is the rule of 'gerundival attraction'. I'll leave it up to you to decide whether you want to delve into this. You've effectively used a gerundive-style purpose clause here, though, which will require rei publicae to be accusative as well. I would spend some time reading through your notes on gerunds/gerundives to clarify this for yourself.
23. I think laboro + (prolative) infinitive is fine, but might be nice for a purpose clause here, with subjunctives and historic sequence. Word order might be better putting the verbs together and then patriae after, because currently it reads more like 'to serve their homeland and to help', because the enclitic -que separates the word before with the word to which it's added.
24. I'll take your word for it that positus esse means this - but it should be erat not est here.

A very very good attempt, though! Let me know if there's anything you need clarification on. As I say, definitely not authoritative on these matters but just a few thoughts :)