id advise you to take it to a proper fitting place (baby bunting, RACV etc..) and get them to look at the installation, they may be able to refit it properly so its reclined, as for the straps they/should be able to loosen the straps so you dont have t lift over, the safe and sound do, another reason to get it properly fitted, they will show you how to use the seat correctly, the people baby bunting use are brilliant.
do you have the instructions??? if you dont then perhaps ring the manufacturer and ask for some to be sent out

ETA i should say ive just turned our seats for DD2 and to make it recline properly the person installing had place rolled up carpet underlay under the seat to make it sit properly, was awesome! and very secure