help on mk1 octavia handling

Hi everyone

im new to forum as just bought my first mk1 octavia vrs estate. Im after some guidence if anyone can help. The car has been tuned up to nearly 300bhp but is on standard suspension. I would like better handling however it needs to be a comfortable ride for the family and have read that arb are a must have and I was hoping to do this on a budget. Is my under standing correct that the mk4 R32 front arb fits the octavia estate at front and if so which arb would work well with this one for rear. A friend advised me the balance of the arbs are important.

I was advised avoid coilovers as ride too hard but maybe worth changing shocks and springs to better after market set? Would you do anything else to improve handling? The car has 120k on it and has a good bit of roll in corners.

Thanks james