Hey, IMO tht list would be quite unsuitable for a 70litre tank. I dnt think u shud really have one angel in a 70litre so 3-4 is unsuitable! Remember this is only one opinion tho and im not tryin 2 be rude! 4-5 gouramis might be ok depending on which gouramis they are, if you are talking about golden or opaline then no but if you were to get 4-5 red honey gouramis or dwarf neon gouramis then it should be ok. Kuhli loaches are a great fish, i bought 4 of them today, they are quite sociable and do well in groups so if you were to go with kuhlis id go for 3 instead of 1. The Otos are a good idea, 2-3 would be good as they are also quite sociable and small growing. I'd advise against the pictus catfish and the female betta as a pictus catfish really needs more than 70 litres and a single female betta just seems a bit mean to me and they can be quite delicate for ur average community tank. The guppies would be great! lol, trying to sound enthusiastic cos it seems all ive done is say no no no, sorry! If you're going to get 4 guppies go for 1 male and 3 females as they are livebearers so the male would be constantly going for the females tryin 2 impregnate them so the more females you have the more rest they each get. You could nothing but 2/3 dwarf puffers in a 70litre. You could try an african claw frog? There are many types of fish suitable for 70 litres, a shoal of rummynose tetras, neon tetras, cardinal tetras, black ruby barbs. Platys/ mollys/ swordtails. A bristlenose plec would be ok in that tank or even some corydoras. Marbled hatchetfish, cherry barbs, golden barbs would be ok. A pair of rams would also be suitable, the options are endless!
Hope ive helped a bit.