Nidan Melbourne

I practice every kata 3-4 times a day from my syllabus in the morning and night (so twice in morning & twice at night). At my school (Goju-ryu) we do Taikyoku Jodan Taikyoku Chudan Taikyoku Gedan Taikyoku Kake Uke Ich Taikyoku Mawashi Uke Gekasai Dai Ich Gekasai Dai Ni Saifa Seeuinchin Sanseru Seisun Sanchin Kata Tensho Kata Every Kata (except Tensho & Sanchin) i do once slowly (to focus on technique) and once full power and timing. Also I film myself in the morning and night on the 2nd run through to help me see what mistakes i made

On one side, i have my school name & style then on the other side i have my name

you are not too old to commence! there are people at my school are well into their 70's who just commenced training and they are loving it. They go even harder than those in their 20's

Hey mate, yes you can (as you put it) "Cross Train". For me, I do both Brazillian Jujitsu (i've done since 2008 through school and then on/off since 2010) and have been doing Goju-Ryu Karate since 2001 (recently became a Shodan Level Black Belt). And I have found that by doing Jujitsu it has greatly helped my standing fight game along with the groundwork. But for Aikido and karate they can go hand in hand so they work quite well. you will understand both martial arts at a deeper level. But you will want to practice at home for karate.