brakes and suspension ....

ok well upon discovering a mulitude of .. rust under my babys rear end have decided that project "dragon" will be taking a different direction fom the original plan .  no point in having a pretty looking car thats fallin apart right so asthetics have been pushed to the back of the line and mechanics to the front ….. !
my problem is i dont know much bout this stuff and so far all the advice ive had from you guys has been spot on and also after having a crash course from andy (new mechanic) about what my car should look like underneath ( first time ive ever looked under a car on a ramp lol ) i feel like ive learnt a great deal , so massive masssive thanks .
Im having a whole chunk of welding doing under the sills and the issue is the worst bits are right by the suspension bits i know its bad but by sat next week and a whole months wages alls well again ..
now whilst being told about brakes and suspension i have been advised to upgrade both if im a) wanting to drop a bigger engine in and b) wanting to put some phat rims on it … which i am defo gonna do .
so i need some advice on makes set ups what you guys have what u guys rate
cheers guys

How do you intend to use the car? If you're just out to beat newer cars away from the lights, the chassis is less relevant than if you want enjoy our excellent local backroads.

im not all about speed …. but
need to change engine coz its running on 240 k which by any standard is quite an achivement and figure that the 1.5/1.6 is gonna be around the same sort of power so id like a bit more ummmpth to her so im going for a 1,8 carb not gti
next year im splasing out on a pair of bbs deep dish chrome 3 pieces in 16" currently have 15" see av on left but my back alloy is buckeled so need to come off now and have found a cheep decent pair of stand ins till i got the ?? to buy the bad boys ….
figured id get the brakes suspension exhaust engine done this year while its in the garage …. just dont know where to start ..