Debian static IPv6 address, RA & DNS issues

Question

I try to configure static IPv6 on my Debian Stretch machine (RaspberryPi with Pi Hole) but I have various issues I cannot handle.

My dhcpcd.conf file :

# Generate SLAAC address using the Hardware Address of the interface
#slaac hwaddr
# OR generate Stable Private IPv6 Addresses based from the DUID
#slaac private

# Example static IP configuration:
interface eth0
static ip_address=192.168.1.100/24
static ip6_address=2a01:aaaa:bbbb:cccc::100/64
static routers=192.168.1.1
static domain_name_servers=127.0.0.1 ::1

Some IPv6 Sysctl variables

net.ipv6.conf.eth0.accept_dad = 1
net.ipv6.conf.eth0.accept_ra = 0
net.ipv6.conf.eth0.accept_ra_defrtr = 1
net.ipv6.conf.eth0.accept_ra_mtu = 1
net.ipv6.conf.eth0.accept_ra_pinfo = 1
net.ipv6.conf.eth0.accept_ra_rtr_pref = 1
net.ipv6.conf.eth0.addr_gen_mode = 1
net.ipv6.conf.eth0.autoconf = 0 
net.ipv6.conf.eth0.use_tempaddr = 2

and finally my resolv.conf (resolvconf is not installed)

# Generated by dhcpcd from eth0.dhcp, eth0.ra
# static resolv.conf file
search mydomain.home
nameserver 127.0.0.1
nameserver ::1

search home # search domain sent by ISP router
nameserver 127.0.0.1
nameserver ::1
nameserver 2a01:aaaa:bbbb:cccc:dddd:eeee:ffff:gggg # ISP router's IPv6
# /etc/resolv.conf.tail can replace this line

eth0 IPv6 addresses :

2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 state UP qlen 1000
    inet6 2a01:aaaa:bbbb:cccc:dddd:eeee:ffff:ccb0/64 scope global temporary dynamic
       valid_lft 1763sec preferred_lft 563sec
    inet6 2a01:aaaa:bbbb:cccc:dddd:eeee:ffff:f540/64 scope global dynamic mngtmpaddr noprefixroute
       valid_lft 1763sec preferred_lft 563sec
    inet6 2a01:aaaa:bbbb:cccc::100/64 scope global noprefixroute
       valid_lft forever preferred_lft forever
    inet6 fe80::aaaa:bbbb:cccc:f540/64 scope link
       valid_lft forever preferred_lft forever

So there is different point I don't understand :

1. I configure static IPv6 address, I block autoconf but I still got an SLAAC IPv6 address (with mngtmpaddr CONFFLAG).. Why ??
2. I block Router Advertisement (sent by ISP router I can't configure), but dhcpcd is still using RA to generate resolv.conf (with search domain home and router IPv6 as DNS)
3. It seems that IPv6 default route is learned by RA : it seems legit to me, but I am not 100% sure if it's the right way to do it

Thanks a lot for your help